Just discovered this thread. First, for calibration I've found that the Tindeman script produces the best results. The Rags script was pretty close. It's probably best to try both once you've shot the color chart, since it doesn't take long to compare once you have the calibrations settings set up as a preset in ACR/LR.http://www.xs4all.nl/~tindeman/raw/acr-calibrator-l.html
However, I still can't seem to get great skin tones in LR/ACR with the 5D. I recently switched to the 5D from a Pentax K10D, and that's one of the few things I really miss about the Pentax. It had wonderful colors and that elusive "film-like" effect that I happen to really like. I get that in daylight conditions with the 5D, but the WB is often pretty far off in tungsten or mixed light.
Someone above mentioned manual settings he/she uses to get good skin tones in LR. If you'd be willing to share them in this thread, I'd appreciate it!