There was a nice story on npr about this a few months ago. here's the link:
http://www.npr.org/templates/story/story.php?storyId=14728208

If it is real (which on the internet is totally debatable), then this opens a huge can of worms regarding privacy. (Once it reaches a full potential.)
Obviously this could be used to better identify assailants from crimes, help people with psychiatric trauma, etc. But it could also be badly abused by interrogating authorities (Guantanamo Bay?).

I'd personally be interested in seeing how different people view the same things; everyone has a slightly different way of remembering events, features, etc. It could provide a lot of useful information on how we store data in our brains!