Social media in the form of ubiquitous user-generated product reviews, where people who have bought and used a product previously can alert new buyers to their experiences with the product, are something that in pre-Internet days had to be obtained from a publication like "Consumer Reports. "
Now, it looks like the next ubiquitous social media success will be the ability to share notes in the margins with other ebook readers. These clickable threads alongside highlighted text in any ebook could become the next big win for social media. And some see the messages as being especially useful for young readers, including students who want to share their notes with their classmates.

In this popular novel, "The Game of Thrones" by George R. R. Martin, a highlighted passage (left) reads "dead men sing no songs" to which Garcia (top right) recounts a similar passage "songs the dead men sing" and Morbus (bottom right) adds "dead men tell no tales."
Students have long had to get together in libraries or dorm rooms to share their notes and questions about specific reading assignments. With ebooks-based textbooks, students will see icons in the margins from their classmates as they read an assignment. When clicked, these icons reveal threaded comments from the other students, the teacher and anyone else who has read the ebook. Even in novels, icons can be left by other readers--hopefully not giving away the plot.
Readers who add margin notes in books can also add links to relevant Websites, online reports, discussion groups, audio, photos and videos. The threaded comment format makes it easy for readers to trace the train of thought of comments and insert their own at just the right spots.
The brainchild of social networking for ebooks was Subtext Media Inc., which recently raised $3 million from investors led by Google Ventures. Subtext Media plans to allow user-generated commentaries to be shared across platforms.
"We want to help everyone get more out of--and put more into--their books," said Andrew Goldman, CEO of Subtext. "Our goal is nothing less than to transform the way people read."
Subtext recently released its first iPad application and 18 demonstration books in the Apple Store with margin comments already inserted by the books’ authors, giving behind-the-scenes facts and revealing secrets about the writing of their books. Subtext also announced that it had struck a deal with Google Books to integrate its social media with all the books in the Google eBookstore.

Good morning from Los Angeles! #ibmcloud
That's it from me! Over to North America.
The data processing of Roland Garros 2012 (#RG12) rests on IBM Private Cloud http://t.co/JUaY1ItM [French Press release]
IBM Accelerates Business from Supply to Demand with New #Cloud Offerings For Smarter Commerce http://t.co/OFxknOb0 [Press Release]
How IBM #SmartCloud Foundation technology powers cloud adoption?
IBM VP @SLHebner explains here http://t.co/sSzfa0O5 [VIDEO]
IBM's Fiona Cullen will present ‘The Power of #Cloud: Driving Business Model’ On May 24 @ Utrecht, Netherlands #cloudforum2012 #ibmcloud
Blog Post: Why service providers should not ignore cloud http://t.co/ZfQyue4r via @eMarcusNet #thoughtsoncloud
Have any #cloudmoment? Share your story with us via Twitter, Instagram, YouTube, Facebook and tag it. See other stories http://t.co/J4ntsaQ5
Sign up now for IBM #SmartCloud Enterprise! No charge for select VMs (only till May 28). More Details >> http://t.co/2LEzOUZC #ibmcloud
RT @HansMoen: See this video from @IBMCloud to learn how to cut costs in building innovation in your business http://t.co/XOyJoFn6 #clou ...