Valve had previously stated that Portal 2 wouldn’t be shown at E3. Well, Portal 2 did appear at E3, but during Sony’s press conference!The game looks like valve is taking the Portal game much farther, and their ambition shows. The 2011 release date on the other hand, isn’t so nice.
By the looks of it, Portal 2 will definitely release on PS3 and probably on Xbox360 and PC through Steam.
There is also word that the PS3 version of Portal 2 will be better, but this is probably only based in the graphics and that really isn’t a big surprise. The PS3 always has better graphics in their games.