Philip Pullman's 'His Dark Materials': Atheistic or pantheistic?

[Richter 8.6]

For those who have read Philip Pullman's excellent fantasy trilogy (The Northern Lights [The Golden Compass], The Subtle Knife, and The Amber Spyglass): Do you agree with some Christians who claim that the series is atheistic in nature, or is it pantheistic (a proposition that the universe, and every bit of matter in it, are 'god')?