Works on Firefox and Chrome, but only if you use Tampermonkey (maybe it works with other userscript extensions for Chrome).
Basically, this script adds buttons/links on YouTube, which provide BBCodes for you to paste in a topic/post. Click on the BBCode button and you get the [youtube] tag with the video ID already there. Click on the Link button and you get a link to it. Simple as.
In the playlist editing pages, it looks like this:
[url=http://www.youtube.com/watch?v=TW641zgPOqQ]Legends of Jazz: Benny Golson - Killer Joe[/url]
I hope this little script helps you out, and if it does, pass it along to your forum friends! If you encounter any bugs, please post here or PM me, so I can try to fix them.
(I posted this here, not WD/P, so more people see it, but if mods think it doesn't belong here, so be it)