The more time I spend on Amazon, and to a certain extent Barnes & Noble, I begin to think of them as social media platforms. These are enormous communities filled with passionate people who are willing to share their thoughts and opinions publically. You may not be able to manage “followers” like you can on Twitter and Facebook but people can certainly contact you.
Assuming of course that you have completed your online profile. On Amazon it is called Your Public Profile and on B&N it is called My B&N. Both are accessible in your profile. Amazon's has more features but just like book distribution you should have a presence on both sites.
You can chose to make it public or private but I suggest public if you want to build credibility and increase the chance you will be contacted. On Amazon any review you write will be here and when people click your name they can get more information about you, such as a link to your website or even your email address should you choose to share it. On B&N people can click a link to send you an email (however they cannot see your address).
One last point is that reviewers can also be a rich source of writing leads for content marketers. Look for books that match your subject and then scour the reviews for good writers, or even reach out to the author.
