When I first decided to start adding my books online, of course I went to LibraryThing. Word of mouth, a northeast locale, and availability made it the place to be. I started loading my books, adding tags, participating as an Early Reviewer and in SantaThing, and enjoyed it immensely. Plus, during my time at the C/W MARS network we used LibraryThing for Libraries to add tags and suggestions to our catalog.
Then Goodreads came along, with much of the same functionality. However, it was prettier, hands down. People could connect easier to other readers, publishers, and the giveaways abounded. I saw a lot of my colleagues and friends using Goodreads more and more, so eventually I went over there. I liked that it had an app for my devices, that I could see what my connections were reading and writing about those reads, and it definitely worked for Reader's Advisory. I never stopped holding my LibraryThing account, but it did grow dusty on its internet shelf.
I cannot say I am part of the pitchfork group against Amazon (maybe a really large fork?). I do use them as a consumer: I am a Prime member, I have the Kindle app on my devices and own an older Kindle which I use for library ebook trainings. Their publishing imprints have produced some books I enjoy recommending (if you enjoy science fiction pick up Containment by Christian Cantrell, excellent stuff), and they have definitely placed themselves squarely within the book market as a force.
Yet I see the concerns, and do concur with them. As stated by Greg Bensinger in the NPR story:
"...there is a concern that Amazon will know too much about its users. They don't want Amazon to know what books they're reading. As it stands today, Amazon knows is the books you bought but it doesn't always know the books you read. Say a neighbor gives you a book and you read it. On Goodreads, you're inclined to talk about that. And now Amazon will know even the books you don't buy and how you feel about them."
The split is there between librarians, too. In Molly McCardle's article for Library Journal, "Will Librarians Still Use Goodreads?", four librarians run the gamut from getting away from Goodreads to giving it a chance. The bailout from Goodreads to LibraryThing has definitely been happening. Yes, Amazon does have a small foothold in LibraryThing, due to its purchase of AbeBooks, but it is not sole or majority ownership. It doesn't have control over data (at least, not that I know of).
I am still waiting to see what happens next. I have seen the experience of Amazon's creep into library lending with Kindle ebook availability. The convenience of getting the format balanced by the understanding that Amazon knows your library history - at least your digital one. The courtesy reminders that your ebook is coming due accompanied by the ability to "buy it to continue reading." Above all, Amazon is a business, and they do it quite successfully, if not without questions and concerns. I fully expect to see this same creep into Goodreads. One of these days one of the Amazon emails will state: "You listed X in your Goodreads profile; would you like to read Y?" That may be my tipping point.