(Nasdaq: AMZN) bought Shelfari, a Seattle social-networking startup, around the same time it acquired Victoria, B.C.-based AbeBooks, which held an equity stake in Shelfari's rival, Library Thing. Now Shelfari is making its way to the Android Kindle.
This move puts even more social-networking features on the e-reader. An earlier upgrade this year let users share e-book passages with friends and followers on both Facebook and Twitter. Previously, the Kindle's 3G wireless connection could access only Amazon's bookstore.

The upgrade came Thursday, making it possible to view book details from Shelfari on smartphones running the Google (Nasdaq: GOOG) operating system. Screen-orientation locking and full-text search both come with the new release, and new features allow Android phone users to add notes and highlight books to sync with Kindle apps on the e-reader or an Apple (Nasdaq: AAPL) iPad.
Shelfari lets you create a virtual bookshelf, where friends can see what you are reading and you can review and discuss them. A Shelfari widget works on most blogs and social networks, including Blogger, LiveJournal, MySpace, TypePad, Xanga, Vox, WordPress, and Facebook.

A quick review of Shelfari reveals a young-adult focus. It was interesting to find that one of my own favorite authors, James Patterson, has a series of sci-fi/fantasy books for a younger crowd: Maximum Ride: The Angel Experiment. The most reviewed books on the site when I looked included Mockingjay, Suzanne Collins' final installment of the Hunger Games trilogy. Among the most commented-upon books was The Story of Muhammad Ali, also written for younger readers.
Members can post their shelves, reviews, and comments. One member had added 363 books, to which someone else commented, "You probably ain't even read none of these." Let's hope his comment was meant tongue-in-cheek, or else I have grave concerns about our young readers and writers.

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