Ike,
Let me start by saying I've never operated either camcorder (how's that for building your confidence in my response! X-D ).
By I've read lots of reviews of those camcorders (and I did stay at a Holiday Inn last night :D ).
OK, joking aside, the reviews say the Canon shoots 1080 interlaced scan, and has the best resolution in its price range. The Canon has HD-SDI output, which woud be useful if you ever want to record uncompressed video to an external device. Otherwise, either camcorder will be recording in HDV, which is highly compressed, thus introducing artifacts.
The JVC shoots 720 progresive scan, and has among the best resolution for camcorders shooting at 720p. Also, reviewers have commented on how much they like the layout of the controls on the JVC.
Bottom line: Both are excellent HDV camcorders. Choose the JVC for the most comfortable, enjoyable shooting experience (all the controls right where you want them), and to get progressive scan. Or choose the Canon for the highest resolution in this price range, and to have the option for recording uncompressed video (when appropriate devices become available).
My own preference would be for the JVC, but I would totally understand someone choosing the Canon. (Actually, when I move to HD, I'll probably go with a Panasonic HVX200, but that's another story. ;-) )
Have fun with whatever you get!
Ken Hull