Double Fine Productions CEO/Creative Director/writer Tim Schafer and Telltale writer/designer Sean Vanaman ("Muzzled!", "Lair of the Leviathan") will participate in a panel at this year's GDC, entitled "Make 'Em Laugh: Comedy in Games". They will be joined by Rhianna Pratchett - daughter of novelist Terry Pratchett - who is known for her work on the Overlord series of games.
This isn't the first time that Schafer has participated in a GDC keynote or panel. In 2004, he keynoted the topic "Adventures in Game Design", focusing specifically on the creation of the cast of the game Psychonauts. You can download a recording of that keynote from here.
Here's hoping that 1. this particular panel will be recorded, and that 2. you won't notice the fact this news is three days old.