Last week we noted that AT&T's femtocell service was getting closer to launch, but that the company was working out a few last minute kinks and still having some internal discussion about the pricing model the service will use. The service essentially creates a micro cell tower in the home, allowing users to route wireless calls over their in-home broadband network. Users improve reception, and carriers get to take additional load off of their local towers.

Several of our readers have written in to note that AT&T is sending out this notice to customers that states the trial is expanding. According to the notice, select users in Georgia, South Carolina, North Carolina, Las Vegas and San Diego can now participate (plug your zip code into AT&T's Microcell website to see if you qualify).

As we recently noted, AT&T says pricing differs by trial region, but indications are users pay $49.99 for the hardware (after $100 mail in rebate), and $19.99 a month for unlimited calling.

There's still indications that AT&T will also offer a less-expensive plan that eats your wireless minutes, which as we've complained with Verizon's femtocell launch, is a good way to destroy the value proposition for the customer. If you're easing the strain on your local towers, and the consumer is using their own bandwidth to make the calls, the service should not be expensive if carriers really want it to take off with consumers.