I'd love to see the user profile revamped; and the blogs feature implemented; I have quite the wishlist in the feedback section lol...
I think a mobile theme that'd be able to "detect" a mobile browser (likely based on its user agent) then not show sidebars and show a very basic design to the browser.
I'd also love it if every displayed link was parsed through urlencode to ensure things don't "break" (such as using []'s in url tags).
I got your PT last night, things have been a little hectic this week with family visiting over the weekend and it being my son's last week in school, but I'll be sure to get to you asap.