Google made some changes to how commenting works on your friends' shared items: First is, if you hover over the name of an unfamiliar commenter you can see their profile picture and the links they've added to their Google Profile. Furthermore, you can click the "Start sharing" link to start sharing your shared items with that person! Second, now, you'll be able to see comments on shared items while viewing All items. You'll also be notified when new comments are made by the small speech bubble icon in your left sidebar, even when your Friends' shared items module is collapsed, announced Google Reader blog.