A handful of minor, but notable, changes to the Chrome OS UI are on their way.
Redesigned assets for the App Launcher and System Tray will be arriving in updates set to arrive shortly. Work on removing ‘callouts’ from menu and launcher tooltips is also underway.
App Launcher
Following the unlocking of the Chrome icon from the left-hand side of the launcher the Chrome App Launcher will be moving into its place.
As well as a repositioning it will also gain a new blue ‘background state’ when the launcher is opened or called into ‘focus’ by a shortcut.

System Tray
The System Tray will also be receiving a revised clicked-state background.

Spikes
When clicking on the system tray, or long-pressing an app icon on the launcher, a small arrow is shown at the bottom of the menus. These are also being removed. Menus will instead appear with flat bottoms, much like the App Launcher on Windows and OS X.
