In addition to PsOne games, Japan has TurboGrafx-16 titles in their PlayStation Store. We confirmed with Hudson emulated TurboGrafx-16 games are coming to North America too.
No specific titles were confirmed, but I would bet on Bomberman, Bonk, and the “Crush” pinball games. Four games have been released in Japan so far: Bomberman ’94, New Adventure Island, Sengoku Mahjong, and Devil’s Crush.
Each download is PlayStation 3 and PSP compatible so you can take Bomberman and (fingers crossed) Air Zonk on the go.