I believe you would have gathered by now that am an ardent user of google reader, as my multiple mails being sent through it would testify. There might possibly be other products that probably do a better job; but then the gReader coupled with the google account itself, has kept me hooked onto it.
Starting yesterday, Google Reader introduced allowing for comments on feed items.
Your reader friends then can comment on your shared items, and you can have a whole conversation around it. You can even discuss about what you had for breakfast, and how bad the traffic was. Not to worry, the comments view are restricted to your reader friends only. Click on the above picture for a bigger view.