So, I've been somewhat confused and amused by the shock some folks have professed that the books are atheistic - Pullman has never made bones about that fact (well, he's now said some "it's only against *organized* religion" type things - but it would leave only a very anti-authoritarian, non-personalistic religion standing... you might get away with being a Taoist). And it's pretty obvious, I think, even from The Amber Spyglass.

But I'm curious about your characterization of the books as dangerous. Sure, if you're set on your kids believing in Catholicism then you should probably shelter them from anything that presents an alternative view (though, I'd suspect, the backlash would be much worse if they are sheltered and then something gets through than if they're exposed to different views from the start). But, I mean, C.S. Lewis has as much of a Christian agenda in Narnia, and I wouldn't consider it "dangerous" to give to my child.

I mean, Narnia (and Dark Materials) is vastly inferior to lots of other fantasy and science fiction accessible to young adults, so I'd want to protect them out of good taste. :)