Sorry to bring up a dead thread, but here's a list of the games Sony has down for sure with the PS1 emulator:
Bio Hazard Director's Cut
Konami Antiques MSX Collection V1
Konami Antiques MSX Collection V2
BishiBashi Special
Arc the Lad
Jumping Flash! Aloha Danshaku Funky Daisensou no maki
Minna no Golf 2
Silent Bomber
Tekken 2
Mister Driller
Obviously, this is only for Japanese audiences now, but, when firmware 3.0 ships out, (soon), Americans will get a taste of the Playstation Online store where you can buy the games. For those who have a PS3 already, (yeah right

), you can download the games from the Store already and transfer them to the PSP when 3.0 comes out.
In other news, the PSP Camera has been released in Japan along with the Chotto Shotto UMD which lets you take Motion JPG, with sound, and take and edit pictures.