Has anyone brought such gold upgrade?

I just discovered this website who claims itself to be capable of upgrading any Hilton account to gold. Is it possible? How do they upgrade it? Has anyone upgraded to gold using this kind of service before?

http://www.hotelvipservices.com/hote...d_upgrade.html

As a life hacker, I am super curious about their method. I don't know if they exploit a bug or something.