Great hack, and thanks for all your efforts. I modified the "vbulletin_textedit.js" file to pull the video file tag directly from the embedded/blog code (vs. the URL) with the exception of Google video, because it does not offer the code. I did this because "Break.com", one of the more popular video sites, does not associate the URL within the embedded file tag.
My users just simply copy and paste the embedded/blog code from Break.com, YouTube, LiveLeak, Metacafe, Yahoo, MySpace, and eBaum's World, which inturn places the proper BB code and file tag. For Google Video, I tell my visitors to use the URL instead, because, as I said, it does not offer embed code.
I'm not a coder, and I struggled through the entire process of trial and error, but I can honestly say that I am very happy with the results. I'm writing this post in case you may want to create an alternate version that would use the "provided" embed/blog" code instead of the URL, or even perhaps have it use both (either/or).
Thanks again for a great hack.