In the leadup to today, we knew that there would be a way to really customize your Moto X, though it was unclear if carriers would have these options. Most of what we had heard was that carriers would have the choice of black and white and that would be it. So, one of the few surprises today was that AT&T would be offering the Moto Maker customization options, and that "other carriers" would join the program later on...
Source: http://www.phonearena.com/news/Verizon-Moto-X-will-get-Moto-Maker-options-later-this-year_id45982
Source: http://www.phonearena.com/news/Verizon-Moto-X-will-get-Moto-Maker-options-later-this-year_id45982