One thing to consider is the viewfinder. If, like me, you prefer to hold a camera up to your eye, rather than at arms' length, some sort of viewfinder is necessary. I have the EVF for the original GF-1, and while it works, having another piece of gear to purchase and keep track of is something of a PITA. And it makes the camera much more difficult to fit in a small bag or waist pack, with the large square thing sticking out the top.
I see that Panny has also announced a new, higher resolution EVF for the new camera. That's nice, the better view is good, but it's still another thing to carry and get in the way (and potentially lose.)
Having been waiting for this announcement, I think I'll order a G3. That camera is around US$615 with the 14-42 lens at Amazon today. I think that will be a useful second camera in the m4/3 system.