It looks like a combination of techniques. Some AE, some...not so AE.
For the words on his body, you might be able to fake it with light-colored text with a blending mode such as add and a displacement map effect, to make it look like it distorts with his skin. You're also gonna have a bear of a time motion tracking it to the body. Perhaps that's part of the reason for all the quick cuts?
Some of it looks like 3d particles in an actual 3d program. However, you might be able to fake it with Particular. Do you have Particular? You could make a precomp with letters and/or words flashing a frame at a time and use that precomp as your particle type. Have it set to be a random still frame.
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Hmm... my idea actually doesn't involve much (or even any) movement, so do you think this will lighten the load dramatically? The idea is to have individuals in twixtor slow motion, so that they can read all the words "coming off" of their bodies. Each person will only be on screen by themselves for maybe 3-5 seconds. Then these individuals will "break out" of their shell of words as they return to normal speed. Hopefully that makes sense.
For this spot, at least, a lot more than AE was used. It looks like they created a 3D model of the body, and used that model to drive the dynamics of the text.
Here's a making-of video -- very interesting stuff: