Although I don't know exactly what that will allow us to do LOL.

Depending on your notification settings, it'll mainly a) email you to tell you what books your friends have added (and show comments/ratings), which I get as a daily digest, but there may be other options, and b) let you click on a book and see if your friends have shelved it and what they thought.

For me, in practice, this mostly contributes to my to-read list growing infinitely faster than I can dream of reading. *g*