First off, my previous MMO-like experiences include World of Warfract (+expansions), Warhammer Online, Lord of the Rings Online, Age of Conan, Hellgate London, Guild Wars and a few minutes of Star Wars Galaxies and Anarchy Online. 
I´ve spent about 10-12 hours in this game so far so these are very early MMO impressions.
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Character Creator
Amazing. If you dream it you can make it. 10 hours into the game Im seeing totally unique and totally cool heroes all over the place. I probably spent a good 1 and a half or 2 hours with one single character when I begun. No other game throughout history can match this character creator if you decide to dive into it.
 
Community
Seems alright. Theres not alot of chat going on and group questing dosent seem to happen alot so far but you dont feel alone. There are plenty of players around and the game dosent feel instanced at all.
 
PvE Balance
Kind of all over the place. Some quests and monsters seems to be way easier for some classes and impossible for others. Its not really clear when you want to get a group together and when you dont you often find youself flattened. A "star" system makes you do less damage everytime you die wich can eventually get frustrating. Quest areas often include large camps with frequent spawns and alot of mobs wich I hate. Many unnesesary deaths. 
There are no obvious and easy to use "health potions" dropped and the out of combat regeneration seems to have a will of its own.
 
PvP Balance
Seems kind of broken. But thats to be expected. There are so many combinations of powers that some people make themselves completely impossible to kill in PvP. PvP combat itself feels kinda stale and totally crazy at the same time. With people teleporting, flying, jumping and throwing crates it can easily get overwhelming. Skills dosent flow together aswell as they should and even tho you are scaled up in level when you enter a PvP instance it dosent help at all if you face players that are really that level. You have no chance of killing anything. PvP Instance queues are very short tho and didnt die on me even at 5 AM.
 
World Design
Boring. I´m sorry, its boring. It draws some on comic books and superhero movies but the world itself is very plain. If you´re an explorer in MMO´s stay away. There is nothing to see here.
 
Game Engine
Seems kinda unoptimized. I dont have the absolutely latest pc but my decent dual core, 4gb of ram and geforce 8800gt should be able to run this game at least aswell as the other new games on the market. It dosent. Input lag when moving my character and choppy load-in of the world itself makes the game experience feel kind of jacked. If you have a monster of a PC that eats mine for breakfast you might not run into this problem.
Turning down graphics dosent seem to have any noticable effect on the choppy engine powering this game
 
Leveling
Seems like you have some freedom for customizing your characer´s skills but the skills themselves seems to come very slow and the fact that there are no actual "armor" to put on that alter the appearance of your character as you level up some of the "carrot on a stick" effect is lost.
 
Sound and music
The game has some pretty sweet soundeffects for an MMO with a unique flavour to them but man, the music drives me mad. Its often stressfull.
Volume on everything is completely out of control when you install the game and you need to tinker with alot of sliders to find an enjoyable audio level. Dont forget to turn music all the way off.
 
Latency
Granted I have a pretty shitty Wireless router so I always have some more lagspikes in my MMO than the next player. But even then the game seems pretty laggy at the moment. Clicking buttons have a delay of a second or 2 and you are attacked by monsters you cannot see until half of your healthbar is gone. And thats not counting my personal lagspikes.