Vince is very much a real person.
But that's the thing, Rob - Vince has never been 'verified'. That is, no one here has met him. And for the verification to be legit, it would have to be by someone who we all know exists...that is, someone who has already met other people on the site.
The two times (that I know of) Vince was to have shown up someplace to meet GetBiggers, he's bailed out and generated excuses as to why he didn't show.
It's possible, however, that he may have met Storm from Mayhem...I think there might have been some exchange between the two, but I cannot recall the full story (Storm's version) on that.