i jumped from imovie to final cut pro, its pretty easy to do the basics, and after you learn it progressively, you can move to advanced stuff (my highschool's video editing class is mac based), but after i knew final cut i moved to prem pro, and had little or no learning curve. so i'd say if you can foot the bill, go with final cut, but if not, i dont know any mac apps! sorry
Mac G5 workstation with 4 gigs of ram, 4x250 gig drives in raid 5. High availability cluster server running centos for a server. 2xCanon GL2 cameras.