In both regional variants, the HD version of Metal Gear Solid 3 is based on the "Subsistence" re-release, which means it has optional, user-controllable camera angles. That version also comes with the emulated MSX versions of Metal Gear 1 and 2, adding two more games to the collection!
Kojima also said that the Metal Gear Solid 2 HD release would be based on "subsistence," by which he must have meant "Substance." He wasn't clear on whether the basis was the PS2 or Xbox version -- a distinction that seems minor until you learn that the PS2 version had a skateboarding minigame that we need in HD. Finally, Kojima tweeted an image of the trophy icons for MGS2 and 3, which you can see after the break.