Here's the Deal...
Obviously the footage isn't MOS. I thought I didn't record any audio but I realized that had the crappy audio from the cameras so I used that. Ladder behind me, if you were wondering.
As far as settings go, both cameras were near identical. The same picture profile (no sharpening, contrast down two notches and saturation down a notch). Both cameras were set to the same color temperature and I used Zeiss ZE primes on both. The 5DMKII had the 85mm and the 7D had the 50mm. This gave approximately the same effective angle of view on both (the 7D was at around 80mm with the 1.6x crop factor).
As far as frame rate goes, they were both set to 30fps. The only difference was that I accidently left the shutter on the 7D at a 50th instead of a 60th. I did a slight gamma adjustment in post to help match them up but other than that, zero color correction, sharpening, etc. was done in post. None. All clips were transcoded to ProRes LT before working with them in Final Cut Pro.
As you can see, the 7D's color is definitely different than the 5DMKII's. They both pulled keys pretty easily, but the 5DMKII was a little faster. I could definitely spend another 20-30 minutes on each and clean them up some more and also add a wrapped version of the BG to create an even more convincing key (DV Matte Pro comes with that plug-in). These aren't flawless keys and I could get more detail in the hair by working on the matte and also fix the 7D's slightly green look with color correction. That said, they keyed almost as easily as the EX1. The last time I tried to pull a key with the 5DMKII I had sharpening on and it was definitely harder than this time.
My overall conclusion is that with the right lighting and, very importantly, a good keyer both cameras can pull convincing & usable keys. The 5DMKII seemed to edge out the 7D a little and it was slightly easier to retain hair detail with that footage. I also like the color on the 5D footage more right out of the camera. It could be the different lenses, but both cameras are using brand new Zeiss ZE primes so that's probably not it. Not the first time I have seen a slight difference between the two cameras. Maybe a test with identical lenses is coming up!
Lighting wise, I did a high centered key (LED 600 Flood without a softbox), with a reflector below. I also used a rim light (LED 256). Sort of a beauty lighting set up. Nothing fancy. Just something to get pretty even lighting over her face. Could be better, but it got the job done.
That's it on green stuff for awhile. I feel kind of icky from all that green and want to go and shoot something that's real!