We're not sure when this feature was added, but Cortana can now do impressions. Simply ask Cortana to "do an impression," or "do an impersonation" and listen to some of her responses. There are not many impressions right now, but definitely try it on your device with Windows Phone 8.1 Preview for Developers. We've tried it on our Nokia Lumia Icon. Head past the break to watch our hands-on video.
Full story from the WPCentral blog...