Ghostcrawler chimes in on game balance and nuance, and frankly makes some excellent points. The one that really surprised me (not in terms of its message, but that he was so upfront in admitting it) is that "Selfishly, we get a lot more out of player posts than we get from offering a Q&A. I don't mind a Q&A from time to time, but understand that 90% of my motivation to be here is selfish -- it helps us make the game better." It's a form of selfishness I can get behind.
We also get some information on why downranking was removed ("The math problem was getting difficult and after many meetings we decided we could better spend our design time on more pressing issues"), discussion on what GC sees players concerned with ("Many players are worried about, e.g. whether their raid buff merits being invited to a raid, which has no PvP ramifications. Many players want to have more CC or CC breaks, which has very few PvE implications.") and there's a very interesting back and forth discussion of Recount and other damage/healing meters and their limitations as a predictative tool. All in all, it's a pretty illuminating thread on how Blizzard designs and interacts with the player base.