Personally the change I'm still plotzing over most in relation to 3.1 is the sheer locational chutzpah of the Argent Tournament. I'm not sure I understand why the northern portion of Icecrown is considered an appropriate spot. It's like seeing some Milwaukee strip-mall developer parachute into the middle of Mordor and exclaim over the retail and tourist opportunities within a 100-yard radius of Sauron's eye. What does the Scourge think about this tournament? Did they get a cut of the concession stand's profits as a means of buying their cooperation? Who else was bribed in order to make this happen? These are all questions to which I think we deserve answers.
Anyway, I seem to be one of the unlucky souls doomed to disconnect every 10 minutes from the PTR (although I'm not anywhere near Dalaran), but I'm sure it'll get fixed. One minor suggestion for all those Druids porting to Moonglade in order to pick up dual-specs immediately; have 1,000g in hand before you do so. As we all know, getting into Moonglade is rather easy. Getting out of Moonglade tends to be rather more time-consuming unless you're willing to burn your hearth in a world newly free of ghetto-hearthing.
Some of the undocumented changes we've actually already talked about, so if you don't see something here but missed our first article, you should find them here.