Yes, yes, and yes! I have had a Goodreads profile for a few years now and find it a handy way to keep track of my reading (if I can remember to post my books!) I have "want to read," "read" (that's past tense), and "to read" shelves. Maybe I should expand the shelves: favorites? by topic?
I enjoy Goodreads for keeping in touch with friends, and what they are reading, and for exploring new titles. But I probably use it for the social aspect, and personal library diary, more than exploring new titles. The recommendations page has not piqued my interest as much as doing key-word advance searches in NoveList has. I'm not sure what kind of appeal factors they use for that, but then I don't find the "read alike" feature on NoveList appealing for me either. It is a fun site.
But, Goodreads isn't just for keeping lists and searching for books. I "attended" a live webcast with author Susan Cain. It was super! And I was invited simply because I read her book Quiet: the power of introverts in a world that can't stop talking, which is very good BTW. I intend to explore this aspect of Goodreads further!