I just happened upon this very youtube link from Reddit in the comments somewhere but it didn't seem to be picking up a ton of discussion. I just wanted to share this with people I know would appreciate it.
I recognized the name, though I don't really know him. Wikipedia says he's also a pianist, it really shows in this video. Also that he tunes his guitars in all fourths - EADGCF (like an extra wide bass I guess). It's funny - I've read about tuning in mostly fifths (see New Standard Tuning), but I don't think I've come across all fourths before. I wonder how it works for when you aren't tapping, I'd expect it to make it hard to play full chords.
It seems a lot of guitarists have started four finger tapping like this. The first artist I ever saw do it was buckethead. It blew me away then and as a casual guitarist it blows me away these days too. I know what they're doing but I don't have the dexterity to pull off dual hand 4 finger tapping.
Have you heard of the Chapman Stick? It's an electric guitar-ish instrument designed specifically for tapping.
It's a very neat concept. I wouldn't mind learning to play it, but they're shockingly expensive, and obscure enough that I doubt there are many resources for learning. They're very cool, though. EDIT: Here's another good one:
Heh it was a bit of music nerdiness. Buckethead really likes to play with dissonance and it's an acquired taste when it comes to listening. You'd probably appreciate some of his more melodic stuff or some of his softer stuff.