Yesterday Forbes announced its World’s Most Powerful Celebrities list, with the number one spot going to Lady Gaga. Now Jeff Bercovici at Forbes compares celebrities’ social media scores to their power rankings, to see who the over- and under-achievers are.

The Twitter overachievers include Lil’ Wayne, Eminem, Eva Longoria, and Steve Carrell.

[T]he overachievers are all rappers, athletes or comedians/comedic actors. No surprise there. Those are all groups who have embraced Twitter, especially, as an environment where they can interact with fans without exposing too much of themselves.

The under-achievers is more scattered, and includes behind-the-scenes guys like Steven Spielberg and James Cameron, and the Hollywood celebrities on the list tend to be A-listers like Angelina Jolie, Jennifer Aniston, and Sandra Bullock. Writes Bercovici: “[Y]ou can sort of understand why women whose privacy is so thoroughly violated by the tabloids every week would pass up the opportunity to give them more fodder.”