Re: that specific weekend, I've been meaning to announce -- the weekend of the 23rd is the first Good Internet conference at Berkeley. Should be a great event for anyone on this list: it's designed to explore the idea of "digital citizenship," i.e. how to use the Internet for good. I believe speakers are confirmed from Wikimedia, Code for America, Creative Commons, Electronic Frontier Foundation, etc.
Here's a link for more details: http://www.media-alliance.org/article.php?id=1974
Maybe a Wikimedia meetup right after, on Saturday evening, would make sense?
-Pete
p.s. How would people feel about a get-together in a couple weeks ... the weekend of the 23rd? Maybe Sunday the 24th? It's been a long time since we've had a casual meetup.