I've only been to one of these, in 2003. It was a good time as I also did the tourist thing in CA.
Is there a theme this year? I'd say start giving the show a retro theme. Start focusing on the classic, classic games, nostalgia and such as the primary theme with anything new'ish as a sideshow. Retro is getting hot and there is no real NG system. Well... Retro is getting hot everywhere except the Amiga market, which is largely ignoring the classic.. That should change.