One of the slickest new features included in Android 5.0 Lollipop isn't really new at all. In fact, it is obviously inspired by something that the Moto X could already do. The feature is called Ambient Display and it is basically just a fresh version of the sleep screen from the Moto X.
Basically, with the Moto X, the sleep screen will pulse when the device is asleep. This pulse displays the time, notifications for messages, emails, missed calls and more. Ambient Display mimics this concept and will be included in the Nexus 6. Reports indicate it will also show up in all versions of Android 5.0 once that starts pushing out OTA.
The pics above are two examples of the feature. Pretty slick!
Source: AndroidPolice