I know,
I said I wouldn't do it, but after everybody told me I really should try it, I went to a shop and bought bioshock. I now played through it, and summarized: It's a nice game with a gamplay similar to SystemShock and DeusEx, beautiful graphics and an interesting setting. And after I've finished it now, I felt like a dirtbag after being presented
the evil ending just because I harvested one single little sister and because I did not save all of them. ;)
IMHO, System Shock 2 > BioShock in nearly any way.