I picked this up last night...
WOW.
I never expected this. This is the book that I though BoED was going to be. BoED is the book that I thought Draconomicon was going to be.
I have not yet found a part of the book that I do not like. Everything seems well thought out and well balanced. the BADD people will be very very pleased.
I especially like the Dragon ageing, twighlight, and death section, and the explanation as to why dragons ultimately gather wealth. The players chapter and the dragon chapters are great. My players have been asking for more dragon stuff and the dragons in the party section will work great. (they want familiars and dragon mounts)
There are rules for Dragon armor, and dragoncraft items. There are also cool elegant rules for raising or training a dragon. (considering that my group's ranger just found, subdued and bound Calcryx, we will see where this goes...)
If you like Githyanki, Dragons as mounts will pique your interest. The spells and feats for both dagons and non-dragons are cool and compliment each other well.
The bit on dragon hoardes is priceless. This is because it further expands interesting ways to make a treasure (not just dragon hoardes) unique.
I think it has a decent shot at an Ennie.
Aaron.