BakaHoushi said: Given the popularity of both series in Japan, I'm surprised a faux Persona-style game starring the Touhou cast hasn't been developed.
(In before speculation as to who would be in the playable core and plot developments)
I think the only thing that really prohibits such a development isn't the lack of interest (as both series are insanely popular) but just the fact that programming such a game would be a challenge and a half. It's not like cracking open the SMT engines and slapping Touhou characters in would be even remotely feasible, as far as I can tell.
Still, a game set in the modern day starring the playable cast summoning the non-playables... sounds interesting.