Im not much into John's stuff as its a bit mainstream for me. But I was watching Clapton's Crossroads 07 the other night and he came on. He had a pretty nice solo on his song Gravity.

Am I the only one that thinks this? I know we have a lot of metalheads here, but I pretty much like all genres.
Yeah Ive got all of his albums, I find it good sleeping music. Yeah hes a pretty good guitarist. None of that blaising solo stuff, but hes created some nice stuff.
I never really liked John Mayer until I heard his stuff that wasn't so mainstream. He did some really good work in a trio with Steve Jordan and Pino Palladino. It had more a funk-rock feel to it.
the Try! album is a blues album....

But yeah, hes pretty much one of the most knowledgeable current guitarists as far as theory goes (that is anywhere near popular). He went to Berkeley in Boston, and you can tell he has a tremendous grasp of theory. Try is a good example of his abilities, and theres no telling (IMO) of how much better he can potentially get.