If you are sharing stuff with friends and colleagues, they will naturally make changes to these items from time to time: ranging from relatively minor changes like adjusting the color or font of something on an Idea Page to more significant changes, like modifying a document or adding a note to a project.

When your buddies change shared items, notifications show up in the lower-right corner of the screen:

The number next to the flower (4 in the example above) is the number of new notifications that you haven't seen yet. If you click on the flower, your Workspace shows a list of all notifications, with little red buttons next to the ones that you haven't seen yet:

If you double-click on any entry in this notifications list, you will jump over to the Idea Page where the change occurred. (And this will reduce the count of unread notifications.) To return to your normal Workspace view, just click on the Back button, or click on the flower again.