No, it's not "just digital". It's subscription-only through Safari Online! You can "stream" books and learning videos from there, but you'd never own one. You cannot buy a DRM free O'Reilly eBook anymore, unless it's from one of those Humble Bundle sales (where the selection may or may not suit your needs). I just stopped supporting O'Reilly when it went subscription only, and I'm guessing there are lots of people and companies with Safari subscriptions that don't really use it as much (compared to the percentage that uses it).