From what I can tell there is support through the s9e media bbcodes pack for xenforo but I'm not sure what else it opens the forum up to. I know Chris has run into problems with other add-ons creating security issues with the site. Hopefully Chris sees this and can chime in.
yeah I know nothing about it, I just know that webm is becoming a big thing for videos lately, and I can't post them as a video on our forums XD