Brian, on GPL inheritance to WordPress theme:

I’m not a lawyer and never will be one. What I do know is that right or wrong, black or white, I wanted to make sure that what Jason and I were doing was in line with WP and the GPL license. It’s probably a gray area, to be honest, but we’ve chosen not to take our chances with the legality of it all.

This. Is. It. Echoing Christina Warren:

The only real debate is about licensing. I think that if the theme developers and WordPress could continue to discuss these sorts of issues in a forum that isn’t a blog post (not that this isn’t great, Ian) and the GPL requirements were better outlined, much of this would be cleared up.