Bipolar rocker John Mayer whose on again/off again flirting with glam blogger Perez Hilton must have hit a rough patch as Mayer heartless (and ironically in Perez style) tore into Hilton’s mental capacity in the new issue of Rolling Stone (Feb 4, 2010 issue).

Here is what Mayer said in his words:

On Perez Hilton:
If you meet Perez Hilton, you realize this is not anyone the world should be scared of. He’s not a very bright guy, and I also think he has some sort of clinical ADHD — he seems to exhibit some sort of post-traumatic thing. He’s uneducated and highly opinionated. It is the worst combination in a human being.

OUCH!!! It took Perez several days but tonight he responded just as fiercely and angrily towards John (via Twitter):

Both John (#12) and Perez (#11) made our annual Most Hated Celebrities of 2009 list. Perez came out on top this year, John naturally was on bottom.