I also came across one of these just now. I was hoping I would be able to read it on my Android device and ended up calling and requesting a refund once I found this thread.
Update: I realized that Google sold the same eBook with Adept PDF DRM, I had to strip it for my use on my device by using the
Calibre plugins. That won't help digamma though, I saw his book isn't carried by Google, so it's unfortunate that this new Amazon format does not support mobile devices...
Further, I just even noticed that some Android apps (txtr, Alkido) will actually work with Adept encrypted books, although I haven't tried it, it was easier to just strip the DRM and not worry about it.
That being said,
Amazon should give the option of having these new books readable with their mobile apps for those who want to, regardless of the (perhaps clunky) user experience.