It's the gear selector for the four speed automatic. Put the car in 'L'ow (right behind drive), and the transmission will drop into 3rd gear if it's already in 4th (I believe it holds the current gear if you're in one of the first three). Then use those buttons to move down even lower if needed. Don't confuse this with the paddle shifters on the new 6 speeds, because the paddles let you choose any gear (within limits based on engine rpms), while this is mainly for allowing things like a 2nd gear start on slick surfaces, or gearing down further for going down steep grades. It pretty much replaced the 3/2/1 gear selector positions that used to be behind most 4 speed automatics' 'D'rive spot.