What everyone has said here is great... I will add to that, my decision was based primarily on frame rates.... The 7D will shoot at 720/60p and the 5Dmkii does not, so if over-cranking for slo-mo is important to you than the 7D is the way to go. It was for me...
Good Luck!
Richard Cooper
FrostLine Productions, LLC
Anchorage, Alaska
http://www.frostlineproductions.com