I agree on Mayer's musicianship (and class), but I think his weakness is his songwriting. It's like giving Barry Manilow the guitar ability of Buddy Guy....Just my opinion, but I like hearing Mayer play with other people or do other people's stuff more than his own.

postscript-- I still love the BoDeans. First discovered them when they opened for U2 on the Joshua Tree tour and have enjoyed every new release since. They fill a niche, and they do it quite well IMO.