Tracking changes in those shared docs on Google Drive just got a lot easier. The folks in Mountain View have added an activity stream to the cloud-based file repository for keeping tabs on collaborative efforts. Once you're inside Drive, clicking the 'i' button at the top right will make the new list appear. Inside, you'll find the flurry of recent activity like moving/removing files, renaming, uploading, sharing/unsharing, editing and commenting. You can also select individual files or folders to view updates for only those items. Google says that the activity stream in Drive will be rolling out to users during the next week.