AbeBooks partially owns LibraryThing, a book social network.  Amazon.com had also previously invested in Shelfari, another book social network.  Abebooks built themselves without venture capital.  AbeBooks made $190 million last year from book sales.

The financial terms of the acquisition were undisclosed.

Update: Tim Spalding, founder of LibraryThing, provided further insight into the deal (see comment #1).

Here is some additional information from Tim Spalding:

- LibraryThing did not have any knowledge of or influence over this deal.
- The majority of LibraryThing is in my hands. Abebooks holds a minority of the shares, with certain notable but limited rights. This situation does not change when Amazon acquires Abebooks.
- Amazon will not get access to your data. The LibraryThing/Abebooks terms are specific. Abe gets only anonymized and aggregate data, like recommendations, and they can only use it on Abebooks sites (eg., Abebooks.com, Abebooks.de). Nothing has changed here.
- Abebooks customers won’t see much a difference. The name will survive and the Abebooks.com site will continue. Both employees and management will remain in Canada.
- LibraryThing remains LibraryThing. We will continue to uphold and advance LibraryThing values, including open data, strict privacy rules and support for libraries and independent bookstores.

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