Wired points out that YouTube itself has installed a button to do exactly this:
The placement of the button is interesting. It’s exactly where the post message button used to be, meaning quick commenters will discover it only when they accidentally click the new button. Hopefully they’ll do this with their speakers up at work.
I logged in to YouTube and checked — yep, there it is! Should be interesting. Not quite the StupidFilter, but getting there… and there’s no place quite as prone to excesses of stupid as YouTube, so every little bit helps…