In addition to the CBS video, we have more from the San Diego Comic Con 2010 Big Bang Theory Panel. Entertainment Weekly reported the following nuggets:
* [Executive producer Chuck] Lorre’s reaction to the show’s move to Thursday nights this fall? “It’s a good thing,” he said. “Given where we are now after three seasons, I’d be crazy to argue with the choices CBS has made along the way. Our job is to make a good show, not program the show.”
* Wolowitz’s girlfriend, Bernadette (played by the hilarious Melissa Rauch), will be back.
* Lorre teases that he [teh character of Sheldon played by Jim Parsons] will have a “very unique” relationship with Mayim Bialik’s returning physicist.
Source: EW
More through the link above INCLUDING another video interview with the cast.