AT&T's promised 3G MicroCell should finally arrive next week, a source on the show floor of the 4G World expo claimed late Thursday. The often-delayed femtocell devices should have a rollout to a handful of cities that are believed to include Atlanta, San Antonio, Seattle and at least one city in North Carolina. An AT&T worker spotted by Unstrung has made Twitter posts (since pulled) supporting at least the Georgia (Atlanta) and North Carolina deployments.

Pricing isn't available, but the 3G MicroCell is a Cisco-made device that, like most other femtocells, creates a short-range cellular link that then uses the owner's home Internet connection to send both calls and data. The Microcell will differentiate itself from others by supporting 3G calls as well as data for those phones that don't have Wi-Fi. Usually these devices have an up-front price and sometimes a small subscription fee that promises extra calling time when connected to the femtocell.

Sprint and Verizon already have their own options, but the AT&T unit is considered particularly important given the extreme data load on its network triggered by the iPhone, especially in large cities like New York City and San Francisco; the nodes would reduce the load on main cell towers in most areas. Carrier files have already suggested iPhone support for the 3G MicroCell as a network choice. [image via mobiquizoid]