I suppose anything with that many eyeballs has sales potential. I'm not sure how the well whole social networking paradigm transfers to retail. In a subculture where people base their decisions on what their "friends" like, if you get a few dedicated buyers, it could certainly have a ripple effect. I don't expect it to displace dedicated 3D merchandise venues anytime soon but who knows.  My unsolicited opinion, I find the whole phenomenon rather bizarre, but it clearly fills a need/want for many, many people.

"Democracy is a pathetic belief in the collective wisdom of individual ignorance." - H. L. Mencken