The Verge reports that, Developer Francois Beaufort displayed a screenshot to his Google+ showing off the notice tray. In the screenshot a pop-up occurs from the lower menu bar showing a collection of notices regarding missed calls, new messages and notifications from Google+. It apparently combines all of Google's service, including Google Voice, Gmail, and Google Plus, into one area for easy browsing.
Image Courtesy: The Verge
Chrome OS users most likely have their lives connected with Google entirely. An easy way to see what's going across their digital lifestyle may be greatly acknowledged.