Motorola has all the particulars in this blog post. It's got a 4.5 inch edge-to-edge display and runs Android Jelly Bean, an older version of Google's operating system. Motorola guarantees customers an upgrade to the new KitKat Android release in the beginning of 2014.
The story here is more about the price than the actual phone though. Most top-tier smartphones cost $500-$650 unlocked. The reason why U.S. customers only pay $200 or so for those devices is because wireless carriers subsidize the cost by locking you into a two-year service contract.
Motorola's promise with the Moto G is to provide a phone with premium features for a price that's affordable to just about anyone.
Here's the promo video: