I am on many social networking sites for authors but Good reads is my favorite. I find that Shelfari has a lack of interraction these days and it's kind of boring, LOL. The only problem I have with Goodreads is they don't run bulletins. I think the bulletin option would be wonderful for authors to let readers know their plans and what's up with them. On Goodreads it's no way to share all that info even in groups. Goodreads needs a way where you can at least send info to your friends like on the Ning sites. That way you can send out messages at once. I wrote GR about this and they said they appreciated my opinion and they will look into it.
By the way, Kare is an interesting name! Would be a great name for a character...hmmm, LOL.
Good Reads is also one of my favorites. Shelfari is another. However, each has it's pluses and minuses. I tend to not be as active on them as I would like, but I try and browse around for interesting books. BookHitch, NothingBinding, and others are also good. There is an entire list of such sites (along with places to list your book) that may be of use. Each one has a small following of readers. Social networks and websites for avid readers, authors, and writers.
It appears there may be two goals here... some authors are seeking ways to generate book sales and others are readers, seeking ideas of good books to read.