Clearly this part holds no surprises: the G1 is smaller in every way, though just slightly in overall length. Lens is smaller and very light. The K-7 has my lightest DA lens on it, the WR 50-200. On the scale the K-7 weighs in ready to shoot at just over 1kg; the G1 so equipped is 600g.
I also recorded the capture sounds on my little Casio with both about a foot above the cam. Sounds were surprisingly similar but K-7 screw focus whines before the shutter while the G1 has a very soft whir that probably didn't reach the microphone.
Clearly the K-7 lives up to the 'enthusiast' label with higher-res screen, the top LCD panel and the weather sealing. Those will be hard to top, but the flip screen on the G1 is a point in its favor. The investment was small, so let the games begin!