I don't get all this pessimism when it comes to game movies, I mean sure there's never been a good game to movie adaptation since... well ever, but you can't just say a game to movie adaptation will be bad just because all the others have been, more factors come into play than just it being game to movie.
There's so much they could do with the story line of Bioshock, not just what little you see of it in the games, but the whole Rapture time-line. It would be so hard to make a bad movie out of the source material they have, Bioshock even as a game was centered around it's story and atmosphere.
Making "Bioshock: The Movie" bad would be like taking the Matrix and making two sequels that have essentially no story, consist mainly of action, sex scene and unimpressive set pieces, incorporate philosophical ideas that have no grounding in the Matrix mythos and have Keanu Reeves continue to play the main role.