Instant updates (or timed updates) would be sweet - a couple of months ago Malone and I were working through a particularly tricky Inquisitor over lunch on a Saturday and it was a little frustrating having to keep refreshing to see if s/he had replied!
Otherwise agree with the suggestion that you get to see the query you're replying to when replying. Typically I will forget what I was answering as I answer.
Oh, and ban this site from my computer at work. It owes me a lot of money in lost revenue.