Are you waiting in hope that WotC will publish another Eberron book? Well, they probably won't, but the good news is that you don't need them to - this is what you are looking for.
This book provides chapters of cultural context for players, to help inspire their roleplay.
This book provides enough information on the more mysteriosu areas of the Eberron setting to almost be a second setting.
And then it finishes it off by providing a number of player options that make it easier to play a variety of Eberron archetypes that were previously difficult to pull off.
If you are a fan of Eberron, this book is a must buy.