From an outsider viewpoint (being neither british nor american) I think that jimmy hit the nail on the head with his first post that British comedy is far more cerebral. I find it far more hilarious and can watch it in reruns far more often. It's just my taste though.
I think one of the main differences is that british comedy parodies daily life and big themes with the same far more wit. It's far more subtle and unconventional.
Let's compare the two versions of The Office. While they are both funny, I think the UK version is much more...painfully true. The American version still tries to make everyone a little likeable. It wants to keep people from watching it because some people are utter dicks, but that was what I thought was the brilliance of the UK-version. It's the quintessial example of Americans romanticizing everything.



























