I've gradually done a 180 of sorts on the Gaiman / Palmer axis. I started off liking some of his books (not all), and not really caring about her work. Not disliking, just not caring.
Then I saw the Art of Asking TED talk, and read the book. And now, I like a few of her songs -- Oasis, Leeds United, and, um, that's about it -- while the last book I read and liked by him was Ocean at the End of the Lane.
Somewhere along the line -- I think Stardust was the first time -- I noticed woman and girl characters don't fare so well in Gaiman stories. The fairy mother in Stardust becomes a shrewish mother-in-law, while the two woman the hero has romantic feelings for are both kind of twits. There's the whole "monstrous mother" thing that recurs in Coraline, Ocean at the End of the Lane, and other stories.
If it doesn't bother you or you interpret it another way, cool, but it got to me.
I think part of it is that both Gaiman and Palmer have fans that remind me the term comes from "fanatical". I said one nice thing about The Art of Asking on Twitter, and Palmer RTed it -- okay, cool, I @ ed her in it. A bunch of people liked the tweet or made little comments back, okay cool. But a couple of people tweeted back to me, at length, and while they were very nice and polite I felt like I was being pressured to join a cult. Ditto for behaviour I've seen at Gaiman book signings.
You could argue it's not them, it's their fans, but they both have it.