Yes, thanks for the advice. I'm well aware of the situation there. I don't see it affecting RC however. I believe RC is GPL v2, which is perfectly ok with Joomla if I understood their stance on the issue correctly.
As for Mambo, I have been testing it on and off for the better part of 2 months and still am not satisfied to the point of switching. The need for more exclusive add-ons, version 4.7 being around the corner, Gallery2-SMF bridge not yet being ready for prime time, among a few other concerns are keeping me at bay for now.