http://www.psxextreme.com/ps3-news/826.html
It's the one rumor that refuses to die, even though it's been denied left and right by the developer themselves. But talks of Bioshock heading to the PlayStation 3 have once again begun, but not because someone slipped and leaked a bit of info. Instead, Official PlayStation Magazine UK mentions the development of Bioshock on the PlayStation 3 numerous times in one issue - three to be exact. Their last tidbit debunks the game being exclusive to Microsoft and claim that it's only a timed-exclusive, which 2K Games has always intended on bringing to "next-generation consoles". And that is actually true, 2K Games did originally announce that Bioshock was in development for next-gen consoles, meaning both the X360 and PS3. But I couldn't find any information stating that the game would be a timed-exclusive for Microsoft
I really want to play Bioshock so I hope it's true.