This month, the story can't be anything else but CPU optimizations and fixes, after Fiora decided that if the code is in the JIT, she will make it faster. Nothing is safe from her. Since the end of July, Dolphin's JIT CPU core has seen a 26% performance boost in the Dolphin Benchmark. That is not a typo.
On the accuracy front, we've got some nifty changes that fix bugs going back to the beginning of time for Dolphin. Some ancient audio bugs bite the dust, some floating-point accuracy are ported into the JIT from the SoftwareFP branch, and we found out that some games are doing things they really shouldn't be doing. If you see a change that affects a game you're playing, remember that all of these changes can be found in the latest development builds!