It's pretty much heresy to say this in the SF community, but I don't really like Neil Gaiman. He's a perfectly competent re-worker of myth, but there's just not that much in his stuff for me. There are other writers who really know how to craft an old story so that it sings in a living voice, and for me, he's just not one of them. There's no there there, as the lady said. It's like watching a mediocre episode of Star Trek NG. Some tepid drama, a little moralizing, some fancy sets, and you're done.
But, and this is a big but, his short stories are much, much better. Maybe it's the enforced constriction, but suddenly it's all there: beauty and terror, wild and alive. "The Problem of Susan" is worth five stars on its own, not only for being as perfectly constructed as one of those miniature cakes you find in fancy bakeries, but for pointing out the big, gaping flaw in the heart of CS Lewis' cosmology - not just as it pertains to Susan. This is no mean feat.
I used to think to myself, when I saw a new Neil Gaiman book, maybe this will be the one that's brilliant. But I don't think that anymore. He's clever, and he's rich, and he's adored. I think he'll just keep churning out more of the same. At least we'll always have "Fragile Things".