We ended up at this new kinda hipster-y burger joint in Central Square after being unable to find parking in Harvard Square to go to Charlie's Kitchen, and not being able to get a table at Green Street Grill. It turned out to be a perfectly acceptable alternative for the burger-minded (which we were this evening).
There was a slightly longer wait than expected based on the size of the line because they've only got a single register with one guy taking orders, but once the order was in, it took maybe 7-8 minutes for our burgers to show up.
Branded "All-Natural" beef (Brandt Farm -- rep for high quality, although based in CA), cooked to order (only slightly medium rare for a medium) my burger was juicy and quite tasty. And a significantly better value than Green Street or the stupidly named Tavern on the Square nearby.