Comment Re:The Million Dollar Question (Score 2) 172
I have a PRS-T1. I've never bought anything from Sony's store (it only existed in the UK for a bit over two years, compared with the eight or so in the US!). To my knowledge, the device supports ADEPT only, and once the content is decrypted once it is forever accessible on that device unless you revoke it (there is no online checking). So, uh, at least content already readable will remain as such on devices already authorised.
Also note that ADEPT has long been broken (it's got a good cryptographic basis, but there's almost no obfuscation in the system, so it's pretty useless as DRM), so it's
Quickly Googling makes it sound like customers had their accounts transferred over to Kobo (thereby losing no content), unless they opted out (and I haven't looked closely to see what happened in that case).