On Friday, I remarked on this a little bit: Amazon recently started up a site showing the most-highlighted passages in Kindle books.

Over the weekend, it occurred to me what this means: Everything you highlight in a Kindle goes back to Amazon.com. I checked with a Kindle user, and we could find no way to turn this option off without permanently disabling the Kindle's WiFi and syncing abilities. I bounced around the internet a little bit this afternoon and came across someone who has written a blog post about this highlighting issue. The implications of this are huge:

...what about when someone starts highlighting specific passages [in the Anarchist's Cookbook] that can steer towards the area of intent? Will Amazon use this information and turn it over to authorities?

Amazon may claim they don’t collect any personal information along with users highlighted passages. But let’s be real. They can easily collect such information and despite what their defense of this practice might be, I’m sure they do collect this type of information. Scary!
[...]
Privacy is the real issue here. Kindle users should expect a reasonable amount of privacy when using Amazon’s product. Whatever the reasons are for readers to highlight a particular passage, it’s only their business, not Amazon’s.

Amazon has never been great about privacy, but this is really weird: It appears that there's no way to tell your Kindle to stop watching what you're reading, or what you're doing with your books, and it appears that there's no way to tell your Kindle to stop sharing this information with Amazon.

I was curious about whether the Kindle also collects information on web searches, too, and so I've called Amazon PR and left a message. I'll let you know if they ever return my call; if they do, it'll be a first. I've also put a call in to Carolyn Brown, Director of Corporate Communications at Barnes & Noble.com, to see what the privacy situation on the Nook is.