I get that, but I think it's very difficult to make an argument that given a new user, it would be interpreted as an interaction cue rather than just visual polish.
The presence of the up arrow is actively misleading, from a UX perspective. It's like having a slide toggle that you have to double tap to activate!
iPhoneOS/iOS has been around for 6 years. 600 million devices have been sold that all have the same ‘slide to unlock’ mechanism. Now that the majority of phones being sold are smartphones, Apple must’ve felt that it’s OK to remove some of the training wheels. Whether that’s wise remains to be seen. Microsoft finally removed the ‘Start’ button from Windows, but that has been met with quite some resistance, from new and experienced users alike.
Few people read user manuals, which Apple knows. It doesn’t even ship a physical user manual with their iOS products (just a thin quickstart guide). There are in-depth user manuals available for download[1], but the percentage of iPhone owners who read it must be negligible. I often meet iOS users who don’t know that double-tap on the Home button brings up the app switcher.
As the OSes on these mobile devices become more capable over time (and the interaction model grows more complicated), users may need to start treating them as computers that require learning beyond trial and error.
Once people treat them as the complicated computers they are, we can start the countdown to post-post-PC devices.
Especially because there is no reason to drop the visual slider, or to make all the visual hints on the screen super low-contrast (on the new starry sky background at least).
The up arrow is to indicate sliding up - but for the control center, not to unlock. I agree that a new user may be surprised. But having seen all three work once - slide left-to-right to unlock, down for notifications, up for control - it makes sense to me.
I've been running iOS 7 for a day now and had some co-workers give it a try -- all of them current iPhone users -- and literally every single one of them tried to swipe up to unlock.
Unfortunately, in my experience so far, this isn't the only case of misleading and unintuitive design in iOS 7.
