I think the basic principle of visual simplicity is going to stick around. I do think there's some faddish elements to the adoption though. I like dropping 3d. Embracing the two dimensional property of the screen seems well founded. I doubt the monochrome is permanent: we can simply convey more information with color. I'm conflicted on the lack of labels. They are undoubtedly useful, but do visually clutter the screen. To speculate I suspect that if eye tracking come into wide usage tooltip like extra contextual information on the focus of attention could take over almost completely.