I was never a fan of the GH1, even with the hack, & much prefer the GH2. I may look into hacking the GH2, but only if it's more stable then it's predecessor, & even then, probably not.
I don't blame Panasonic for not allowing higher bit rates. First this is not part of the AVCHD specs, & more importantly, they need their cameras to be stable, & perform, under all conditions.
The GH2 is a great compliment to the AF100, as they share lenses, & cut together well, but I mostly use it for 16:9 B-Roll stills, or whenever a larger videocam would be inappropriate.
Some of GH2's downsides are lower bitrates at 720/60 then 1080/24, & lower dynamic range then the AF100. The small from factor can be great for walkabouts, or sneaky-cam, but the lack of mass can also lead to shaky footage, & I'm not confident handholding lens longer than 25mm ("Normal") unless they're capable of Image Stabilization. Of course a shoulder rig could be attached to avoid the shakes, but at that point I'd rather use the AF100.