I initally assumed this was a fairly basic roll-call of dragons, and frankly expected a lot of reprints of the old Ed Greenwood articles on "Wyrms of the North", originally printed in Dragon magazine and updated on the Wizards of the Coast website. Actually, it is much more than that.
Firstly, I have to mention the cover - a ravishingly beautiful (if slightly grisly) depiction of a gigantic red dragon obliterating a party with its fiery breath (and flip over to the back cover, where the sole survivor watches in horror from the shelter of a pillar as her compatriots are roasted - brilliant).
Secondly, this actually doesn't really contain much on the Wyrms of the North stuff at all - instead the reader is redirected to the said website for this stuff. Much of what is there is actually new content, which seems only fair for an expensive hardback book.
Thirdly, it actually looks beyond the period of the Rage of Dragons (as depicted in the trilogy of FR novels by Richard Lee Byers) and is, to some extent, moving the FR world on in time a bit, at least with respect to the impact of those events upon the Cult of the Dragon, the Church of Tiamat and events in Unther and Chessenta. We are no longer in the Year of Rogue Dragons, Sammaster is destroyed and Tchazzar is reborn.
In brief, the sections of the book comprise a history of dragons in Faerun, including the rivalry between Tiamat and Bahamut, a brief description of a few important dragons and dracoliches, and a smallish though interesting section on draconic motivations (effectively dividing them between predators, who have a small impact at a political level, i.e. the archetypical "hoard-sitter", and schemers who are much more active in schemes and machinations at a regional level). Next there is a chapter on the Cult of the Dragon, and how recent events have changed it and its leadership. After that, the Church of Tiamat and the its impact on Chessenta and Unther are described (including a brief detailing of Unther as a region). Another sets out various, less important draconic groups, including the Moruemes of the Nether Mountains with their hobgoblin army and the Silver Talons, a group of draconic paladins. The next couple of sections set out "draconic lairs", including traps, hazards (like dracolich slough, animated bits of undead flesh that have fallen off a dracolich) and monsters, spells and magic items (including a number of minor and major artifacts which can be found in the hoards of specific dragons). Finally, there is a comprehensive listing of all dragons mentioned in the FR literature, including novels, with indicative descriptions.
One caveat - a degree of reliance is placed upon the owner having the Draconomicon and, to a lesser extent, Races of the Dragon too (while some are fully statted, a number of dragons are described along the lines as using the same statistics as "the ancient green dragon on page xxx of the Draconomicon", and a number of prestige classes and feats from this publication are used, for example in Tchazzar stats, who is a terrifying CR40!). This doesn't bother me (I own them both) but it might some people. However, you can probably use it without these, though it might involve a bit more elbow grease to create the relevant nasties.
Overall, I like this. It has good campaign ideas, a few of the dragos really make compelling long term villains, and it pushes forward the story of Faerun a bit further.