For one thing the concept of Fame as it relates to the importance or relevance of philosophers is somewhat dubious.

However if Fame can be applied to philosophy. Andy Warhol is undoubtedly the most famous philosopher of fame, and he is not on this list.

Je suis d'accord.

This is hardly something something I'd want to appear on my alma mater's web site (as it does here for ucalgary.ca). Perhaps there is a uHollywood.us? Further undermining the list is the journal which provides its single reference:

Schulman, E. 2009, "Measuring Fame Quantitatively. IV. Who's the Most Famous of Them All?" Annals of Improbable Research Online, February 28.