AFAIK drm version 3 still isn't cracked, but there's some epubs without drm, and most with drm is possible to get with older drm for backwards compatability reasons.
I'm not sure what the status of drm circumvention for fair/own use is in the US - I think there was a case that opened up for viewing/backing up dvds, but if not - this is still illegal, which partly defeats the purpose of buying through Amazon.
it's interesting but some kindle books I've purchased have a little blurb at the beginning of the book that says something like "the publisher has distributed this book without DRM"
I always wondered if the kindle file was actually unencrypted.
Possibly. I vaguely recall this... But I'm not sure if there's been other rulings, or if ebooks or media-as-a-service has been in the courts after this.
I'm not sure what the status of drm circumvention for fair/own use is in the US - I think there was a case that opened up for viewing/backing up dvds, but if not - this is still illegal, which partly defeats the purpose of buying through Amazon.