A Healthy Dose of Escapism
May I direct your attention to the MMORPG titled City of Heroes?
It's currently in its Beta testing phase and allowing pre-orders. The graphics are impressive, the rationale for cordoning off sections of the city is acceptable, and the assigning of "missions" in the superhero genre is also plausible and fun. It really makes you feel like you're part of a group of super-powered heroes working together to fight the enemies of the citizens of Paragon City.
The costume creation mechanics are neat - they really give you a wide variety of body shapes and costume colors, patterns, and "flair". The fact that you retain that distinctive look during gameplay is all the more impressive.
A friend of mine mentioned that the term "kill-stealing" doesn't really apply to the world. Given the "super-hero" setting, it didn't make sense for the champions of the city to argue "HEY... that guy was mine!" Well, maybe sometimes... but not ALL the time. You're supposed to be heroes! So, they've just agreed on certain protocols (such as offering help, or saying things like "thanks... but I could've taken him myself!" to keep things friendly) for now...
As for character creation - it's very versatile and allows for a wide variety of superpower combinations, but keeping the power levels low initially... and then growing as the hero gains experience.