Few more details about the PSP game has popped up in the latest issue of Newtype.
"Suzumiya Haruhi no Yakusoku (Promise of Suzumiya Haruhi)" will be an ADV game as stated earlier. As you walk around the campus and come across events, you get to play some mini games. Nothing about whether the story will be the same as the show or not but, it will feature full voice acting by the same Anime cast.
The "new element" announced a while ago will be the "Motion Portrait" system. Apparently character expressions will change in real time which may mean you won't see the usual slideshow "tachie" portraits that you get in ADVs.
Fun stuff.
