I'm looking for the combined, collective wisdom of LiveJournal.

I've been toying, for the last six months, about the idea of doing a documentary (actually, lately I've wanted to do two: one on trans issues and one on Haiti). But I think I need actual camera experience. What things should I keep in mind?

How important are:

• An external mic jack?
• An internal hard drive versus record-to-DVD?
• Size?
• Anything else I'm not thinking about?