Joss Whedon has been busy with "The Avengers" and other side projects lately, but that doesn't mean he hasn't been thinking about a followup to "Dr. Horrible's Sing-Along Blog." In a recent interview, Whedon teased that work on a sequel could begin as soon as this summer.
"We are hard on it. It's been a really tough year — couple of years — partially, I'm happy to say, because of work," Whedon said. "We're stuck, basically, at this one part in the process. All of us are looking at this summer