Disclaimer: This is written from a Japanese use-case scenario. 3G/Near/App experiences may vary for European or US launches. For those interested in importing one, all the UI elements can be set to a variety of languages.
So after a couple weeks with my 3G Vita, I feel I have had enough hands-on time with the device to offer some initial impressions of the device: where it succeeds or falters, what unexpected surprises it had for me, and some hands on time with a few games I've managed to have the time to play on it. This will be a lengthy post, so feel free to skip to the sections you may be interested in.
Probably the area that needs the least explanation, all the hardware specs have been available for people to pore over for quite some time, so I won't go into specifics of every feature that the Vita hardware offers. The actual device is a fair bit larger than a standard PSP, and won't easily fit in a pocket, but does fit very comfortably in your hands with notable soft grips on both sides. The touch-screens on both the front and back are smooth and glossy, which makes them very victim to picking up fingerprints, I recommend screen protectors on both sides (which are already available). The new analog sticks are really responsive and comfortable, way way better than the sticks that were on the original PSP. The entire device feels very smooth, light, and comfortable even if it's larger than previous PSP incarnations.
The screen is absolutely fantastic, everything looks really crisp and vibrant on it (it's several times the resolution of the PSP screen), and it gets very bright at maximum brightness settings. If you are using the device on the go, you won't be using it at that max brightness though, but the screen seems to hold up relatively well. This may actually become my goto portable video device when I don't have my iPad handy, things look just that good on it. Hardware-wise, this is probably the highlight of the entire device.
The battery life, while it could certainly last longer for my tastes, isn't quite as bad as I was worried about. My usual use-case scenario (3G on, 3/4 brightness, 1/4 sound) seems to get me just under 5 hours of battery life. The device can charge from empty to full in just over two hours, which is actually pretty nice. Nicest part about the battery is that should the battery die, the system will suspend itself so that you won't lose any playtime at all, the system will pick up your game exactly where it left off.
The touchpads...well, they work just fine. Just like you'd expect from any modern smartphone or tablet type device, I haven't had any issues with the touch at all. I haven't played a whole lot of games using these input mechanisms, because I am not that infatuated with touch controls for games, but they work for navigating the interface just fine. The back touchpad takes some getting used to, since you are using a touch screen that you can't actually see, but it's been put to some pretty creative uses in some games. I'm not sold on touchpads or gyroscopic controls at all yet, otherwise I'd probably be doing all my gaming on iOS devices.
The cameras suck, you're not going to ever want to use this device for taking pictures or anything like serious video work. They are there for AR type games and other novelties, which they manage fine, not any kind of serious photography. This probably doesn't come as any kind of shock, and if you were planning to buy this device for photography, you will want to look elsewhere.
Internet connectivity works great, both on 3G and Wifi. 3G speeds seem comparable, if not faster, than on my iPhone (likely due to it being on a better cell carrier here in Japan). This is going to vary greatly based on your carrier though, so take into account what service provider is carrying the Vita in your region before you get the 3G model. It picks up my house wifi with no real problems in configuration, and actually seems to get a better signal than my PS3 on the other side of my room.
All internal storage is performed using Sony's proprietary memory sticks, which are in short supply here in Japan right now. It's a bit unfortunate they don't use more standard formats, as memory sticks ARE more expensive than formats like SD cards. All games currently run between 500 MB and 3GB, so take that into account when planning your storage solutions.
Vita Software and Apps
Next up is the Vita software and UI itself, which is something readers are going to have far less experience with. The UI itself is designed entirely around touch, and you are going to have to use the touchscreen to navigate the Vita UI, even if you intend to only use analog controls within games. It's a very intuitive and simple interface for anyone that's used to touch-screen controls, and actually contains a pretty cool mini game collection/tutorial (called Welcome Park) that introduces you to all the Vita software has to offer. Interestingly enough, you can even get trophies by completing this tutorial.
The main screen you'll see is very reminiscent of an iOS or Android device, with a grid of bubble like icons that displays all installed games, options, and apps. Flipping through the different screens full of apps is done just like you would on any smartphone device. Tapping one of these bubbles will expand into a menu for the game or the app, with the ability to launch the game, visit the game's website, launch directly into multiplayer, or expand the array of options for settings or network functionality. It's all pretty intuitive, and anyone that has used a touch device before will feel perfectly at home navigating the main UI of the Vita. The Store shares similar touch UI elements, and is pretty easy to navigate, which is good as that is where you will probably be downloading just about all your games.
The web browser included with the Vita is...sufficient. It's not a device you'll want to do extensive browsing on because it renders pages incredibly slow, I have no idea why. The on-screen touch keyboard is actually really solid, so it makes the browsing a bit less painful, but I don't find myself ever using the browser except to launch specific game sites (which I usually launch directly from the game app menu). The included niconico app that ties to the niconico website (it's like a Japanese youtube) works MUCH smoother than the browser, and is actually quite a pleasant experience. The twitter app is actually really nice, reminding me quite a bit of the Twitter app for the iPad, which is a really good thing. Since I have a 3G model, I find myself swiping over from a game I am playing to check on twitter without having to pull my phone out of my pocket. Other apps include the usual bevy of movie player, music player, and photo manager. All sufficient, nothing really incredible here.
Near rounds out the suite of apps included on the Vita, and is perhaps the most significant. I'll write an entire blog post on this later, because there's actually a ton to talk about within Near, but it's essentially a geographic social network for the Vita (similar to what you may experience from a 3DS street pass) that will show you what anybody near you with a Vita is playing, their PSN info, and more. At the time of this writing, I can see that within less than a KM of my location there are over 30 people playing Minna no Golf. Some games like Katamari even automatically share gifts between players that are playing katamari within a certain radius of each other. For privacy concerns, of course all these features can be turned off/on as you desire.
The Vita also supports cross-game chats/party chats, and batch group messaging. These all work great, and it really makes me wonder WHY Sony hasn't added this to the PS3 yet, since they'd be very welcome features there. Since you will be on a unified PSN, this means that you can message your friends that are playing on their PS3s, see what games they are playing, etc. There is trophy support on the Vita too, for those who were unaware.
There IS a huge problem with the current iteration of the Vita software, though it's only going to be a big issue for a very small percentage of the population. You can only have ONE PSN account tied to your Vita at a time, which makes it more of a personal device than something you can share between multiple people. As somebody who has both a Japanese PSN account and a US PSN account, I have to decide which account I want active on my PSN. Anytime I want to switch accounts on my PSN, i actually have to wipe the Vita and log into an entirely new account. I have no idea why Sony does this, but it's extremely frustrating for those of us that have multiple PSN accounts. If you have multiple memory sticks, a semi-workaround exists where you just store all your US data on one and all your Japanese on the other, and switch back and forth. Be very aware of this issue before you buy your Vita though and expect to set up multiple accounts on it.
I haven't got a chance to play everything out there yet, there's a pretty significant library of games available at launch. There's a handful of games I've really had much playtime with. These are of course, what matters most when it comes to the system.
Minna no Golf 6: The most popular Vita game in Japan right now, for a very good reason. Known as Hot Shots Golf in the West, this game is a ton of fun. It uses a wide range of the Vita features, from motion controls to touch pad to network connectivity. I don't even like golf particularly much, but the game is such a fun full-featured package that I couldn't help but jump on the bandwagon and tee off.
Uncharted: The Golden Abyss: I can't say a whole lot about this title except that it feels amazingly like a proper PS3 Uncharted game, which is quite the accomplishment. All of Drake's personality and witty remarks are here in full force, with characters that seem like they came right out of Naughty Dog's studios. Production values are astounding, screenshots don't do this game justice until you can actually see it on the Vita's screen. The analog controls are really tight for both shooting and platforming, and never really seemed to get into my way. There are optional touch controls for platforming elements, but you can forsake them for analog controls if you prefer, so I never really used them. A few points in the game require you to use the touchpads for certain puzzle-solving elements, but these parts are few and far between and work well enough that they never really bothered me that much.
Blazblue Continuum Shift Extend: A portable version of one of my favourite fighting games, this game is basically identical in every way to the arcade version of Continuum Shift. The game looks gorgeous, animates beautifully, and controls really well. The game does offer touch support, but I really can't recommend playing such a twitch-based fighting game with touch controls, it just doesn't work. I'd recommend using the very comfortable d-pad for input, though the analog sticks do work reasonably well if that is your preference.
Disgaea 3, Lords of Apocalypse, Ridge Raiser, and Army Corps of Hell are on my list to pick up, but I haven't had the time to get them yet.
The Vita is a really impressive machine backed up by some great software. It's not going to convert somebody from hating portable games into a believer, but it's a pretty solid update for people who already greatly enjoyed the suite of games that the PSP offered. Enhanced network capability, hardware, and social features really make this a much more advanced system than its predecessor. There are a few design choices that I do not understand at all, such as Sony's insistence on limiting each Vita to a single PSN account, but these can always be rectified in a later update. Hopefully this will happen by the time of a US release.
If I left anything out that you are interested in, by all means ask and I will be happy to try to answer any questions. I could write a ton more on about any subject here, but I wasn't sure what areas people were interested in specifically. I'll be trying to get some more game time in with a wider variety of games (Gravity Rush Demo!) and can answer some questions about those too.