Good read not really any spoilers I think...nothing that upsets the books. Anything about Orr I'd already read on the wiki, and this doesn't reveal anything much.
Just some fascinating insights into the nature of the elder dragons. BUT...there are possible hints to things, as in connections to the elder dragons, that may be found out in game through tomes etc. But I don't think they're spoilers...I'd thought about them all myself already. It's not like hints haven't already been given elsewhere.
Very nice! Well-written and informative. I'm going to be picking up the Guild Wars books this weekend to try and satiate my lore-hunger, although I fear that after reading them I'll just anticipate the GW2 release that much more.