I must admit I know much less about consumer video than pro video or still photography - I can't recommend one cam in particular, but here's a bit of advice:
-Hi 8 is cool. Don't run out of tape, or batteries!
-Buy small, but also rugged to take a beating. Don't let yourself be talked into top of the line cameras, ridiculously great zoom range, or bells and whistles you don't need. You want every basic function to perform flawlessly, and will really-really need little else.
-Once en route, don't be obsessed with your video camera's security. Enjoy.
-Don't even try to record everything. Shoot sparingly but meaningfully, and never, ever show unedited footage unless you don't really care about your audience.
-Easy on the zoom.
-By all means buy early, shoot with it, get used to it, know it by heart.
-MOST IMPORTANT: Learn how to use a camera! I don't mean operating it, I mean timing, composition, travellings, zooming, resource shots, the works. Go to a nice book store and buy a book or two on the basics of video recording. Do not neglect this, it's by far the best piece of advice I'm giving you.
-Did I mention "easy on the zoom?"
That's it from me. Everyone else, anything you can add, especially on which camera?