GM announced today that three of its new models will come with a button on the steering wheel that will activate Siri in the same manner as holding down the home button on an iPhone. The cars' MyLink infotainment system will connect to the iPhone via Bluetooth. Drivers will be able to do things such as make voice-activated hands-free calls, play songs from their iTiunes library, send a text message, use their calendar, and ask simple questions, such as the latest sports scores.