--He just seems like he'd be really fun and have some great stories, though.--

He was very much like that. Definitely one of those guests who just seemed to enjoy being there.

--...the main guy was fairly rude in his disinterest and obvious lack of enthusiasm for being there. So I didn't go to the panel. With his attitude, I'd suspect it wasn't great.--

Urgh. Probably not. I'm glad to have only encountered one speaker like that and, instead, found more people who were genuinely excited for their topics.