Joss Whedon says to expect more of Dr. Horrible's Sing-Along Blog in some form or another, but won't say what exactly.

"It is my intention that we will see more of young Billy and his horrible schemes, and I have a very specific idea of what that's going to be, but until I'm sure how I can roll it out, I will say nothing except that I'm definitely pursuing that," Whedon promised in an exclusive interview.

"I mean, there are two things that happened. There was Dr. Horrible itself, and there was the Internet sort of event, and I'm pursuing both of those kind of separately, in the sense that I want to tell a Dr. Horrible story, but I also want to continue trying new things on the Internet," Whedon added, somewhat cryptically. "And it might not be Dr. Horrible, just because I want to keep it fresh. I don't want to just do the same thing because I did it successfully once. So ... it feels like two very exciting avenues have been opened up by that experience."

So ... what kind of Dr. Horrible? DVDs? A movie? "Puppets," Whedon says, with tongue in cheek. "Shadow puppets is the latest idea. ... Beyond the fact that I'm excited about pursuing that story and that world, I love the fact that, you know, you can make something and just put it up without, you know, without having to reshoot the whole thing. Tra la!" (That last bit was an oblique reference to Fox, which got Whedon to dump his initial pilot for Dollhouse.)

Stay tuned!