Joss Whedon just confirmed here on his Comic-Con panel that he plans to do at least another episode of Dr. Horrible. His relevant quotes after the jump; more details once the panel wraps.

Updates: Below the jump, details on the Dr. Horrible DVD…

A questioner asks, “What would a Part Four of Dr. Horrible be like?”

Joss sort of takes a deep breath. “The idea is that there will be another part –

(interrupted by huge cheers)

–so we’re not gonna tell you about it yet.”
He goes on to talk about why he’s excited to continue the webseries:

“I’m older, and balder/wiser than when I made Firefly, and I approach things differently. I take it one episode at a time. And any episode we don’t get out…I can make stuff on the internet now!” Cheers.

“Besides the fact that we all had an enormous amount of fun, this was designed to be a model for a new way to put out media, an artistic community that involves all of you guys, and all of us, and maybe not so much… other people.”

“I’m not trying to bring down the studios, I do still work there, as we all do, and I’m grateful for it…but things are changing, and its really important that as things change, they change for the better, and Dr. Horrible is about that, its about putting power in different hands — THE WRONG HANDS.”

DVD Details: Jed Whedon (I think–a brother of Joss for sure) said the following: “You’ve probably heard of Commentary: The Musical. If you haven’t, well...Commentary: The Musical. The songs are written.”

And there will be a contest. “We will take video submissions for the Evil League of Evil. No longer than 3 minutes, like you’re applying for Survivor or something, We’ll put the 10 best videos on the DVD. We’ve got a couple of things to do first, like the soundtrack…”

Joss: “Soundtrack should be available for download within a couple of weeks.”

Also: Nathan Fillion named a site where you can have “your own functional Dr. Horrible van remote.” No, I don’t know what that would actually mean in real life, either, but play around with it and share your findings…