The update will allow the customer to use their phone to select their items, charge the purchase to their iTunes Store account, and receive a receipt via email, which can be furnished to an employee as proof of purchase. This process will greatly enhance convenience for the shopper who wants to run in and pick up an accessory without waiting for assistance from an associate. It is rumored that this service may be available as early as November 3rd.
For shoppers who want a faster shopping experience for higher priced items that are not available on the sales floors, such as iPods, iPhones, and Macs, Apple will be expanding its ship-to-store option for purchases made through the online Apple Store. This service is already available in the Bay Area and New York City and is expected to rollout to the rest of the U.S. very soon.
source: MacRumors via PCMag