Terrific episode. People seem to want more and more out of WordPress themes as time goes on, so there's certainly a market for more premium themes--but not everyone will be able to build a theme-based business as opposed to selling a theme or two in someone else's marketplace.

But my burning question is--if I reworked a StudioPress theme for a client, am I supposed to release that into the wild (or give a copy to StudioPress) because it's GPL, or is it legitimate to leave that as something that only the client uses?