Stick of Truth has been in development at Obsidian for quite some time. The unique part of the game is that it has been closely developed with South Park creators Trey Parker and Matt Stone. The game was actually in development before it even had a publishing deal.
It is expected that Ubisoft will be showing more of Stick of Truth at E3; and at that point it is likely that we will be able to better gauge how close the title is to actual release for the Xbox 360 and PlayStation 3. No next gen conversion effort for Stick of Truth has been announced so far.