Check out these two posts at IMAO
Funny is in the Birth Defect of the Beholder by spacemonkey about some idiotic blogger that doesn't understand why conservatives don't have a sense of humor. Make sure to check out the comments too.
Why Don't I Find People Who Make Fun of My Worldview Funny? by Frank J on the same topic, he goes more into what even makes funny, "funny". Check out the comments here too.