I just found this little snippet in the comments on Andy Bitterer's blog.
Richard Stiennon says: "I always advised vendors that were having trouble getting heard above the noise to have sales discover if their customers were Gartner clients. Then have them schedule inquiries...(a) typical Gartner analyst does fewer than 10 end-user calls a week. If they get three calls on a new technology and discover they all selected the same solution *that* is influential."
Which I was thought was interesting.