Yeah I know somebody who has been buying kindle books for years planning to remove the DRM at some point, but it's never a great time. It finally was a good time for it and he discovered that he no longer can (even though his proof-of-concept test years ago worked fine). I would be beyond irritated if I had to isolate my Kindle from the internet and hope a vulerability is found that I'm capable of using, just for the chance to liberate books I purchased.