Now Google is announcing an update to Drive, which brings new, and much needed functionality to its offering. The service allows for easy collaboration on projects, but until now, it was difficult to track the various changes being made. Google is adding an activity stream to solve that issue.
via Betanews: Google Drive update adds an activity stream.
This will be helpful for keeping track of who is working on what as we share Google Drive documents. Watch for the feature to appear over the course of the next week.