I voted for UI before reading through this topic. It really doesn't matter to me either way. My users aren't interested in blogs since my main forum is just a small personal site with a few friends logging in. They are interested in having an integrated chat page as am I. I also want to echo Allen's request for moblogging being integrated, that's one of my favorite features at the Groupee.com mothership.
Personally, I think we we should go with the blogging for those of us owners that want to better monetize their forums with that feature. And maybe throw in a moblog system and chat to round it out before tackling a major UI overhaul.
