ZPizza isn't really new to the DC area. I'm surprised you just heard about them. They are one of my favorites when it comes to chain pizza places, but if you get a bad location it will ruin the whole experience. I'm also glad that their ingredients are very natural but tasty all at the same time.
DC area? I wouldn't know about that. I don't visit the suburbs much except on rehearsal nights and for concerts. But I rarely eat out there. Occasionally we'll go to Annapolis, or Old Town Alexandria for dinner, but usually for seafood, not for pizza and not for a chain. As far as I know, there's only 1 Zpizza in the District. It's relatively new.
So far, the closest pizza I've had resembling NY pizza I grew up on is at WeThePizza. They may also have the best meatball in the District, which makes for an incredibly good meatball sub.
There are other good pizza places, but I don't get over to that side of town anymore. Zpizza is downtown. I wouldn't ordinarily try chain pizza, but the Living Social deal seems to be a pretty good reason to try it.