A great product, with excellent Eberron information, and most/all of the archetypes can be adapted to Forgotten Realms for those not running Eberron yet. I would even allow the Sovereign Domain cleric, if my player had a reason for being an omnitheist. Though in Forgotten Realms, there would always be a question of how they are recieved. Off-hand, but used when needed, or heretic? :)
There are however, a few archetypes that seem a bit overtuned; the most obvious is Progenitor Spark.
All in all though, worth the purchase.
[4 of 5 Stars!]