It has just come to my attention that he has indeed used this for spam. He is also using it for profit too.
Would this not be considered a breach of forum rules?
It's soundly in the gray area as far as self-promotion goes, but I think I'll allow it this time since we can't be expected to police the content of YouTube videos. If it were a link to his personal site (or if he starts promoting it directly in other threads) then I'd definitely call it a violation.