We just reported about the video demo of Windows Phone 8.1’s Action Center(notification center). Here is another short video providing the glimpse of dynamic lockscreen feature and the new media control feature in Windows Phone 8.1.
In Windows Phone 8, you can set artists image as lockscreen background when playing music. But in Windows Phone 8.1, there will be dynamic background in lockscreen with artists image, name, etc, from Xbox Music app. Also, the updated media controls when you press volume keys will show album art and there is also a new way to seek your music by sliding at the bottom of the control as opposed to the button mechanism in Windows Phone 8.
Update: WPCentral claims that the above video is fake.