Pilmer

No unlockable sexy schoolgirl outfit for the Little Sisters a la RE4. Why play a game over if you can't get a taste of Nippon-edophilia?

Player choice? What, more ways to shoot scary monsters? Alien Hominid had loads of funny hats. That's choice.

My favorite thing about BioShock is the amazing mo-cap for the flopping fish. Well, either that or the audio logs of all those unlucky Rapturians (Rapturites?). It amazes me that that feature from System Shock 2 hasn't been picked up by more development teams -- it adds so much ambiance.