I contacted kindle customer service via email and received the response below. It is not a scam but there was no mention of what it was or what the cost would be at the end of the trial period. After receiving the email I wrote back and asked them what the future charge would be at the end of the trial. I recently received a second email below which says it will be free and the original email was incorrect.
Hello,
I confirm that this mail is not a SCAM mail. It is sent from Amazon Kindle Team.
The Kindle Compass is an editorial magazine designed to help customers get the
most out of their Kindle reading experience. It is delivered wirelessly to
Kindle devices, free of charge.
We are currently delivering the magazine to a random subset of Kindle customers.
Customers who wish to unsubscribe from The Kindle Compass can do so from a link
in the last section of the magazine, or from the Manage Your Kindle
Subscriptions page at
www.amazon.com/manageyourkindlesubscriptionsAt this time we are not able to subscribe additional customers, but we look
forward to making The Kindle Compass available to more customers in the future.
Thanks for your interest in Kindle.
Thank you for your recent inquiry. Did I solve your problem?
If yes, please click here:
http://www.amazon.com/gp/help/survey?p=AH611W6GONSO&k=hyIf no, please click here:
http://www.amazon.com/gp/help/survey?p=AH611W6GONSO&k=hnPraveena M
This morning we sent you an e-mail regarding The Kindle Compass, a new free
publication built by the Kindle editorial team that we’re piloting to a small
number of Kindle customers.
This e-mail incorrectly referred to The Kindle Compass as a subscription with a
free trial. We built it to always be free for customers, and you will never be
charged for it. We apologize for any confusion.
If you wish to unsubscribe from the pilot for The Kindle Compass, you can do so
from a link in the last section of the magazine, or from the Manage Your Kindle
Subscriptions page at
www.amazon.com/manageyourkindlesubscriptionsAmazon.com Kindle Support