Freemium executed well with a small detail at Vimeo (tabbedthinking.posterous.com)

That's just one of the many points that you have to get right to get a Freemium business working. Summing up Vimeo's success to just that one point (the fact that they, basically, advertise the benefits of their premium product in a tangible, omnipresent fashion) is really a gross over-simplification.