If the wikileaks guys are smart enough to have made it this far you can bet they've already set up a "dead man switch" torrent file somewhere that will self-tweet and self-publish the video x days from now if they fail to check in. PR stunts aren't their style- this smells like either a disinformation campaign to discredit them or a smoke screen for something else. Fortunately there's enough intelligent, vocal people watching this ordeal at this point that it can't be swept under a rug if they disappear. good luck fellas- you're leading an important charge right now.
Panama and Hong Kong have several ISPs that are outside U.S. influence. You never know really. Use Tor to upload it to Youtube. See if Google helps out.
Panama outside of US influence? We invaded them not that long ago, the current political leadership there were participants in the events leading up to and following Operation Just Cause. I rather doubt that much of import happens in Panama without tacit approval of US authorities.
It sounds like there'd be some risk involved..