I'm trying to upload a short vid to YouTube, and I've tried numerous times since last night - but it just won't go through. It uploads anywhere between 0 and 5% of the the clip, then just stays there, even though it says it's still loading.

The video format and filesize are fine, and my firewall (ZoneAlarm) isn't saying there's anything wrong.

Any ideas on what's wrong, and how to get around it?