He's got a very good point, but I think that as with anything in the movies, if it's done well, people will want to see it.
If it's crap, then it's crap. Right, Wolverine Origins? (you horrible piece of shit)
Also, as an aside, I thought this was going to be from Bryan Singer and I had this wonderful zinger lined up "No, Bryan, just your career after your mishandling of Superman"
There. I've had my fun.
In fairness to Vaughn, though, he's right- this is definitely a danger. As long as this doesn't affect Batman 3, I don't care
Personally, though, there is going to be a market for this stuff in future although its inevitable that it's going to contract to an extent.
If anything, I think Marvel Studios might very well be the ones to kill the golden goose if they misjudge the release of their Thor and Avengers projects.
They seem to have a habit of driving a character into the ground, after all... I really don't like what they've done with Punisher, and they're in danger of mangling Deadpool.
Which would be plane tragic as he's going to become overused and safe if they're not careful.