Plus, that same video showed people that you can use the volume buttons as shutter buttons which is something most people likely don't know about.
At the end of the day, UIs are unnatural interfaces. Skeumorphism only makes things worse. So UX design can only meet the user half way; intelligence must be employed to get the most out of an interface.
I see these videos as akin to using a TV remote instead of getting up to change the channel: people are lazy, so appeal to that laziness (along with the whole "here have some pro resources" thing as well) as a form of sales.
It's brilliant.
To unlock an iPhone you had to slide the lock, which is similar to how you'd open (old) doors. Isn't in this case skeumorphism helpful?
This is sort of what I was getting at - I just found this article, but it's quite balanced. http://www.slate.com/articles/technology/technology/2012/11/...