Am I right in thinking that there's a potential opportunity for Amazon here? If they provide audio playback support for the Kindle they could sell combined Audi

Am I right in thinking that there's a potential opportunity for Amazon here? If they provide audio playback support for the Kindle they could sell combined Audio/eBooks that maybe even highlight the spoken text and turn in time to the audio? I think this could be good for both audio books and ebooks as well as when considering the implications for educational books (such as language books or religious study materials).