NextGen are reporting that there are rumours that 2KGames are planning a followup to Game of the Year winner, Bioshock. The underwater FPS was prasied for it's storyline and immersive visual style, yet left hardcore players wanting more, and the prequel sounds like it might be set to provide.

The rumours spring from job postings for the Bioshock studio, relating to an unnanounced product. Apparently they are focusing on writing the story of how Rapture, the underwater "utopia" came to collapse into what it is in the original game.

Sounds fairly interesting, at least.