Analyze Words is a new and super useful tool for determining other people’s personalities via their posts on Twitter. Developed by James W. Pennebaker, a University of Texas Professor of Psychology, along with his daughter Teal, Roger Booth and Chris Wilson, the program analyzes tweets based on not the “content words” but rather the “style words” — like articles and prepositions — to determine the mental state of the author.

Basically this means that you can plug in anyone’s Twitter handle — including your own — and watch it ranked in Emotional Style, Social Style and Thinking Style. We’ve been playing with this for hours. After the jump, check out some of our favorite tweet analyses of famous people.

Aha! Just as we suspected -

Lady Gaga is pretty upbeat, but even more angry, arrogant/distant, and has a slightly more analytic thinking style than an in-the-moment one.

Rivers Cuomo is fairly depressed but personable, with an analytic thinking style.

Al Gore, on the other hand, is VERY depressed, arrogant/distant and thinks in the moment.

Chuck Palahniuk is extremely angry, extremely arrogant, and medium in the moment. Huh.

Jonathan Ames has medium levels of everything, because he is a chill guy.

Karl Rove has high levels of both upbeatness and worriedness, and, inexplicably, is pretty plugged-in.

Tracy Morgan is very, very worried. But personable!

MC Hammer is extremely upbeat, “plugged in” and a sensory thinker.

Passion Pit is quite upbeat too, although more than a little worried, pretty plugged in and sensory.

Even though Sarah Palin technically no longer has enough words for a precise reading, we couldn’t help but report that she is depressed, ranks extremely high in both arrogance and “spacey/valley girl” and is an in-the-moment thinker (aka not good for the future).

Oh and FYI, Flavorpill is upbeat, plugged in, and oh so sensory. Mmm.

For a more detailed description of how this works, check out the article on Good.is.