New domains are a lot of fun to design. If anything, we'll have to make sure we don't do too many.
While the domains support the warpriest with class features and new options for the paragon path included in Heroes of the Fallen Lands, they also include 2 at-wills and an encounter power at each slot that any cleric can select. So, that's 9 new powers for any cleric.
Even still, I have to admit that I'll be sorely disappointed, even frustrated, if most if not all of the domains in Divine Power don't get warpriest treatment.
That's not needless symmetry - it ties in directly with story.
Especially given that the iconic warpriests in that book's artwork don't even worship gods that are mechanically supported by the currently available warpriest domains.
The Erathis and Raven Queen worshippers depicted deserve some lovin'.
I understand the difficulties that balancing dozens of new powers presents, and that an increased array of options makes it easier to slip into power creep; but this being what is basically
the cleric class in the essentials line, and having domain selection as a defining element for them...
A framework has been laid down, and right now only the facade of the house of gods has walls. There's a lot to fill out before it'll feel like home to people who want to play an essentials cleric who doesn't worship Kord, Pelor, or Moradin.
Don't get me wrong, I love the uniqueness this new framework gives worshippers of specific gods, (Great work there! Mage schools rock too!) but I'm uncomfortable if domains are only going to be trickled out in dragon articles once every few months, never seeing print, and some perhaps not coming at all.
(-P.S. If you're interested in reviving legacy names for future products, might I suggest a player-oriented
Faiths and Pantheons alongside a DM-oriented
Deities and Demigods? Boxed set? Just a thought.

)