Not Quite as "Groundbreaking" as promised
Before I continue, Dishonored isn't a bad game. Not by a long shot. More or less my disappointment with the game comes at it's length, which for your average $60 game today, should be at least 10 to 12 hours in length. At least, that's all I ask for. If it's a game like Halo or Call of Duty, I know that it'll have some fantastic multiplayer out of the box that will also give me countless hours of replayabliity. However, single-player games are always a gamble these days.
The biggest aspect of Dishonored that drew me in initially was the whole "play your way" approach to the game. Yes, there are different outcomes for how you could do things, but it never gets as intuitive as something like Hitman. In Hitman, everything has always been about stealth. Sure, you can finish a mission in a very lethal way, by killing everyone, but this always affected the outcome. Here in Dishonored, you can go in and kill literally everyone, in my first playthrough, I did.
The game really only has two ways to play: high chaos and low chaos. In high chaos, you can kill everyone, run around like a pyschopath, and pretty much do what you want to. In low chaos, the game takes a more interesting approach. By going into each of this games seven missions this way, (yes, seven missions), the game becomes much more of a thrill. Sneaking around, making sure you aren't spotted by enemies, it totally did bring me back to earlier Hitman games. The thrill of not knowing if an enemy is going to turn around and catch you always brings enough of a challenge to any game, and quite a thrill, but playing this way doesn't really do more then drag the game out longer then it really is. At the end of my high chaos playthrough, the game took me about six hours to complete. Now granted, I'd be ok with this in something like Call of Duty. But this is a single player game only, and that's just really not acceptable in today's age.
Secondly, not to be "that guy", but the Achievements really discourage you to use any powers in this game. Sure, there are some that encourage it, but when three to four of the achievements in this game revolve around you playing through the game without killing, being detected, and not using any power upgrades, that's downright shameful in my opinion, and a totally missed opportunity.
Speaking of powers, so that's where this game differs from something like Hitman, in fact, feeling more in line with the Thief franchise. After a quick introduction that sets up the events of the game, your character, Corvo Attano, you then are helped with your escape from prison after being framed for a murder you didn't commit. Once out, you meet up with "The Loyalists". After setting up yourself as an assassin, out to get your revenge against those that set you up, you awake to get special powers. This part of the game I felt was kind of poorly thrown in, just to give the game an excuse to be different from other stealth games. You can get a variety of different powers, but the obvious favorite is "blink". With this ability, you can essentially "ghost" yourself around for a pretty decent distance, especially if upgraded. There are other useful abilities, some come off useful, and others are wasted opportunities. Possession is probably the best example of a wasted opportunity. At tier one, you can posses animals. Well useful quite a bit, possessing animals such as rats or dogs isn't really all that useful. Worse, once you unlock the ability to possess humans, all you can do is walk around with them for a brief period of time. It would have been fantastic to be able to use weapons, or choke out other enemies or something, but the game never goes that far. This feels like a gigantic cop out more then anything else. Other powers are a bit more useful, such as the ability to see throw walls at enemies (Dark Vision), and "Bend Time", which lets you go all Matrix on people. I have to also mention that the power of wind (I forgot what it's officially called) where you can use a wind power to knock down enemies or doors, also extremely useless. It's fun, but doesn't really do much for you.
The final point is that the game doesn't really offer the most fantastic conclusion, at least on the high chaos playthrough. While I'm only mid way on my stealth playthrough, I have heard it has a better ending this way, but still. Not giving a decent wrap up to the story hurts something like this, especially when it comes off as more of a tech demo for something more.
I did enjoy my time with Dishonored, although it was brief. I liked the setting of the game, but overall the game feels more like a six hour tech demo of something much bigger, something that we could be waiting for on a bigger sequel, that's for sure. While it doesn't become an instant classic like Assassin's Creed, Hitman or even Thief, Dishonored does a decent job of trying out some new concepts and delivering an enjoyable enough experience, just not one I can recommend at $60 price point. You are better off waiting until $30 price point to pick this one up. You will enjoy it, but don't expect it to have the most lasting effect on you when it's all said and done.