Desktop notifications for Chrome and Chrome OS started with a very basic design. Later on, they got a little bit of polish along with the Chrome OS UI. When the Ash launcher was introduced (the settings menu on the bottom-right corner of your Chromebook) it started looking really good.
Now, Google is bringing in more style and content in to the notification popups. Here is the official, developer version of this change.
This takes the existing message center code for Ash, and refactors it
into two layers – a system-specific layer (WebNotificationTray) and a
platform-independent (modulo Views) layer (MessageCenterTray). The
WebNotificationTray is responsible for rendering the tray icon and
noticing system changes that cause differences in rendering. The
MessageCenterTray delegates responsibility for rendering the message
center and notification bubbles to the WebNotificationTray.
If that was Greek to you, here is a commoner friendly version of it. Currently available under the flag Enable Rich Notifications, this feature can make Chrome notifications more stylish, and rich in content.
This is currently available only on Chromium builds (download the latest here) but we will soon see this coming to Developer builds.
François Beaufort who dug this up from Chromium code thinks that this is one more sign towards Google Now which will soon land on Chrome and Chrome OS. And that does make sense. The beauty of Google Now is in the notification cards and Chrome needs to be capable of rendering those beautiful Google Now cards before they can bring this feature in.
This may be a single step for Chrome. But for Google Now, it is a giant leap!