When options are hidden behind strange gestures, off-screen menus, and obscure icons, how are people ever suppose to find them without prior knowledge?
Todays GUIs are stuck in some uncandy valley, too much css, not enough value.
Better question, why not just stick with a GUI element that can be described succinctly? A gear perhaps.
In fact I'm writing this on Firefox, which has one of those things in the browser UI...
Similar to lots of other technical or jargon terms, it's not a good description for a (new) user.
I do feel that the swipe from the side menus are really unintuitive, and better left tethered to an on-screen (even if it scrolls off) button/icon in addition to swipe interaction, at least until it becomes very common.
A lot of the changes are because of size constrained devices, and a return to the concept that someone can only really see or think about a few things at a time. Then again, using OSX, Windows and Linux UIs on a regular bases, along with differences in apps that are cross platform, I may be too lenient of a judge here.