According to Motorola, the update will improve overall photo quality, such as white-balance and color accuracy. Specifically the phone should exhibit better exposures in outdoor and strongly backlit environments. That sounds like a tweak to the Moto X's HDR mode and BSI sensor to me.
Additionally, Motorola says the improved Moto X should snap photos faster and have a more nimble autofocus, especially in low light. This is a welcome fix since when I reviewed the Moto X I definitely felt a delay between shots, an issue its rivals the HTC One and Samsung Galaxy S4 don't suffer from.
Other performance quirks the company expects to have ironed out are speedier switching between the front and back camera, along with various fixes to Touchless Control and call quality.
Be advised, though, that today's update will only hit the T-Mobile version of the Moto X and not the carrier-branded models of Motorola's smartphone. While a company representative explained this has nothing to do with the T-Mobile Moto X having an unlocked bootloader, I find it telling that the only X enjoying fresh code also happens to be the one sold directly by Motorola unsubsidized. Sorry AT&T, Sprint, and Verizon Moto X owners, you'll have to sit this one out.