I have 2 canon h1s, and I edit hdv from these cameras primarily in final cut with my aging ppc dual 2gig g5 with only 1gig of ram. Rendering takes a while, but it's not too bad. Working on a feature length at 24f.
That being said, I wouldn't touch full hd on this system. It's not even worth buying a machine for that unless you're using it a lot (working as an editor) with the rate computers progress. For short-term projects, I'll rent a top of the line computer with sata raid.