Stu Maschwitz replied to my email:
So basically, we will have to compress 60 fps on that measly 17 mbps bitrate, and we will have to go through the same ordeal we have to go with the HV20/30. No, thanks.[...] the GH1 shoots true 24 and then adds 3:2 pulldown. You'll be able to extract clean 24p, but it's an extra step that could have been avoided, and your files will be bigger with the redundant frames. [...]
He also mentioned though that the camera has film modes regarding gamma curves, so this might (or might not) fix the contrast problems.