Bio Shock is an excellent game. I played the PC version and I loved it. Its full of new freaky weapons, and the graphics is fantastic, I think it uses the Unreal Engine 3. Play it at night and you'll have nightmares.
I already loved the Xbox360 version of this game but the Ps3 version seems to be even better! I really look forward to it! Let's hope that it comes really soon and wipes the floor with the Xbox360 version as it is to be expected. Because the Ps3 is the more powerful console and it would be a shame to let this power go to waste!