Looks like Chevy is adding them to almost the entire fleet...

With modern transmissions using electronic controls, the ratio selection can be managed better to minimize fuel consumption by avoiding excessive hunting between gears. The controls can also take advantage of ratio skipping on these transmissions to go from sixth to fourth or even third when needed for acceleration. As the remainder of Chevrolet's lineup is replaced over the next couple of years – including the Aveo, Impala and HHR – all of the new models will be using at least six-speed transmissions.
A dozen 2011 Chevrolets to offer 6-speed automatics