Looks great. I expected it would be a bit bigger. The APS-C size sensor puts a practical limit on how small zoom lenses can be, even with the designers having the freedom of no set flange-sensor distance. Think about the Sony R-1, brighter by a half-stop at the wide end, it was a pretty big lens. This looks about the same to me as the Sony Nex 18-50.
The Sony 16mp sensor makes the slower speed of the lens a little easier to take.
Not sure if I'll get this, but I'm happy to see the system expand. I'm really looking forward to the A16 M mount module, and the Luigi case for the GXR with M mount.
I had the nex 5n for a while and there's a LOT to like about it. But there were a few things about the GXR that brought me back to it. Like a grip, built-in intervalometer, built-in flash, hot shoe...
And nice to see that the ugly design syndrome hasn't spread from Pentax to Daddy Ricoh.