I like Jonah Goldberg, and I dislike Margaret Cho's politics, but I find Goldberg's insistence that Margaret Cho isn't funny completely obtuse. You can't judge Cho's humor from the written text of her act. Most of the humor is in the voice and the facial expression. If you can set aside your aversion to her politics and watch a DVD or two, you would understand why it doesn't make any sense to read the text of her jokes and pronounce them unfunny. Try watching "I'm the One That I Want." It really is quite hilarious.
UPDATE: Thanks to Jonah for linking -- and for writing "Althouse is cool." (I should put that in my sidebar.) And, as long as I'm updating, let me add another example about comedy that this point about Cho reminded me of. The new Seinfeld DVDs have interviews with some of the supporting actors, including one with the actor who played Uncle Leo, a character I find hilarious. He first appears in "The Pony Remark," and the DVD has a nice interview with the actor, Leo Lesser. Lesser talks about auditioning for the part. Everyone laughed at his reading, and he looked at the script and wondered: "What are they laughing at? There's nothing funny in what I'm saying. I repeated a couple of more lines, and they laughed again. And the entire time I'm thinking what the hell are they laughing at? There's nothing funny here." Then the clip of Lesser delivering those lines in the episode is played and we hear the lines: "You wanna hear something? Your cousin Jeffrey is switching parks. They're transferring him to Riverside. So he'll completely revamp that operation. Do you understand? He'll do in Riverside now what he did in Central Park. More money. So, that's your cousin." On paper, there's no joke, but every time I hear Lesser say those lines it cracks me up. It's comic acting, not joketelling. Much funnier than jokes, really, I think.