I don't favor the Panny's, so I've not tested them at all. From what I've read (so it's all second hand): The Pannys do AE on the focus point (+1 for Panny), but the touch screen is pressure sensitive, vs. the Oly which is capacitive. In short, you have to push harder on the Panny, the Oly you just graze. For fast action, I think capacitive will be better. But, this is based on guess work. Maybe someone else knows more?
(Not that you asked, but I don't buy Panny's because a) I don't like what their noise pattern looks like, b) I generally don't like their colors, c) I don't like that they never have stock available, d) I don't like their games with batteries -- new batteries everytime, and their chipped, so no generics, e) I prefer IBIS, f) I really like the EPx styling. So, they might be a better camera, but for me they are a no-go)
edit: Thinking a bit more about it, I would think a GH3 with a capacitive touch screen might be the pinnacle of an m43 camera. I'll bet with the EP3 out, look to Oly to switch to a different touch screen type, and include it on the GH3. Just a guess.