Apple has announced that Siri will integrate with certain auto voice control systems once iOS 6 is released. The "Eyes Free" system, as Apple calls it, allows Siri to be activated with a button mounted in the steering wheel.
Now, GM has announced that the Chevrolet Sonic and the 2013 Spark will support the feature. The auto manufacturer hasn't provided much detail beyond the initial announcement, but expect more details "within the next 12 months."