It is not something you go around shouting “This is a life changer!”, but IMHO it has its own dignity and it is going to gain more and more importance in the future releases.
I am talking about the Visual Studio Notifications Center. It is something which is based on the Connected IDE, maybe the first example of its integration into Visual Studio, together with the Roaming Settings.
It is a small icon on top of the IDE…
…which opens a Notification pane:
IMHO it is important because it could be the notifications’ hub for informative content (help installation, license expiration) but updates as well.