Google released official Google+ extensions for Google Chrome. These extensions will help you to see all Google+ notifications right from the browser and a Google+ button to share web pages.
Google+ notification extension shows if you have any new notifications in Google+, the extension button will turn red and shows the count of notifications you have. Once you click the button a dropdown window will appear and shows the notifications similar to what you see with Google bar when using any of the Google services. Clicking on these notifications will show you a quick view of the activity without leaving the browser tab you are on.
Google+ button extension adds Google+ button to your browser, using this you can +1 any page and share it with others.