According to the supplier list for the 2012 Verano, there are going to be four powertrains available for the car between now and 2020. There will be three gasoline burners: a 2.0-liter available the entire time and a 2.4-liter that fades out in 2015 in favor of a 2.5-liter. Also in 2015, the 2.5-liter hybrid becomes available. This is all based on information taken from the Supplier Business trade magazine.
There has never been an official mention of an eAssist Verano, which is GM's favored green touch today. We'll have to see if GM opts to give the Verano an mpg-boosting shot in the arm between now and 2015, but what we're looking at here appears to be a full hybrid setup.