It’s more than six months before Joss Whedon’s new series Dollhouse premieres on Fox, which means we’ve got nine months before Fox sets off howls of rage throughout the blogosphere by refusing to renew the series regardless of how much Whedon’s fans beg, plead, and threaten. But in the interim, Joss is not resting on his laurels. His new online venture, Dr. Horrible’s Sing-along Blog, is just about ready to be rolled out. Dr. Horrible is a musical starring Neil Patrick Harris, who’s demonstrated his chops on Broadway, and the as yet unheard vocal stylings of Nathan Fillion and Felicia Day. The project sounds, umm, interesting:

“It’s about a low-rent supervillain [Harris as Dr. Horrible] who’s trying to get into the Evil League of Evil and defeat his nemesis, Captain Hammer [Fillion] and work up the nerve to talk to the pretty girl at the laundromat [Day],” Whedon said. The idea occurred to Whedon a while back, and it was co-written by Whedon and his brothers, and brother’s fiancée.

This has the potential to be very good—or, at least, very creative—or very bad indeed. And still pretty creative, most likely. Whedon plans to introduce Dr. Horrible in three 12-minute segments, as soon as he can work out some sort of financing so the cast and crew can get paid for their efforts. Dr. Horrible isn’t a full-blown Joss Whedon series, but it should hold fans until Dollhouse begins its brief run in January 2009.