Yeah, I've been pretty happy with it. Its faster than the X100, not near as fast as the new m43 cams, but plenty fast (then again, I'm pretty satisfied with the X100 AF, so I may not be your best witness on this). The face recognition is very good, but it can fool you into thinking the AF is faster than it is. I was checking it out street shooting from the hip and I'd bring the camera up after the shot and the face detection box was still nailed on someone's face, but when I'd zoom in on the actual shot, that face wasn't nearly in focus - so it FOUND the face very quickly but still needed more time to focus on it than I was giving it. Which isn't unreasonable - on most cameras I wouldn't even try this trick, but when I use my epl3 like this with either the 12 or 14mm lenses, it seems to nail focus almost every time, which is a fairly astonishing trick for shooting blind from the hip. So now I use zone focus for street shooting with the X10, but the AF works fine for everything else I've tried it with. And the couple of times I tried it with burst mode, it seemed incredibly good, like it somehow worked faster and better. I actually had a few burst series on the street where I was also shooting from the hip and it seemed to nail focus on every shot - I'm not sure I can understand this, but the results were pretty clear (no pun intended).
-Ray