It sounds like one of those Apple-esque terms where they invent their own term for things which already seem to have terms. "End-to-end encryption" is already something even the technically unenthused possess the effort to comprehend (and I'd say it's one of the top few they should, in terms of general importance and usefulness), but this new capitalized term seems to refer specifically to most major types of data stored in iCloud, now including iMessage conversations, photo libraries, and device backups. It's all one feature, and it's either on or off. ("Off" still means that certain sets of data, such as health data and passwords, which Apple has already been protecting with end-to-end encryption, are still protected that way.)

• Apple's press release

What stands out to me is that the system emphasizes to the user that it will become entirely the user's responsibility to save their own password or set up recovery contacts to decrypt their own data, including that which Apple is storing for them. If they lose their own key, they're truly stuck. In terms of a distinctive feature, that seems to be the location of the drawn line: you, as someone who may or may not be technically enthused, decide whether you care to make that effort.

It seems like the choice of line-drawing location shows that Apple has heretofore considered their average customer to come with no guarantee of technical enthusedness, which seems consistent with Apple's history as a company that makes computers for everyone, for "mere mortals," what have you. The first Macintosh arrived at a time when most computers came with large manuals, sometimes with their own fairly nice-looking binders, and the expectation was that the user was willing, if not eager, to read them, or at least refer to them regularly, in order to learn how to use the computer. This new feature, a difficult one not to applaud from any standpoint, shows Apple knows some customers retain at least a wisp of that readiness to approach and use their own possessions with that attitude.

For Apple, it also seems noteworthy that this is a distinct feature at all. Apple could merely have expanded existing data protections without placing responsibility on the user, or they could have tossed the responsibility to every user. For any kind of switch or option to exist for the user in a consumer-focused Apple product, its existence must be well justified. In this case, the feeling that there are indeed two kinds of users, and that individuals may come to "convert" between them, must have been a pronounced one.

(Also from a statement today, apparently Apple isn't going ahead with one of their previously-announced "child safety" features which involved using on-device image recognition. That's still a discussion, but a different one.)