Okay, so Project Icarus is the self-deprecating codename for Irrational's next Bioshock title: Bioshock Infinite.
After much waiting - and some shenanigans within the gaming press regarding the breaking of embargoes - the details are as folllows. Actually, the main fact is that it's no longer watery, it's set in the sky. In a huge city called Columbia.
As ever it's an FPS, but this one is set in 1912. You are ex-Pinkerton agent, Booker DeWitt. Your role is to rescue Elizabeth. The thing is, that's not the whole of it. You have to escape the city by combining your powers with hers.