>Does anyone know if the D7100 uses some kind of Gorilla Glass >for the screens? I'll never go back to the plastic cover.
I think Nikon has been using an outer layer of optically fine, extremely protective glass on all its mid-range to high-end DSLR LCD screens since the D3. I used a GGS screen protector on my D700 for a while, but removed it because I didn't like the thin black border. Haven't used a screen protector since then (four years ago). I do an enormous amount of walking with my camera hanging on a strap from my right shoulder. No screen scratches or abrasions on my D700, D7000, D800, Fujifilm X100, Fujifilm X-Pro1, etc., etc.
Factory installed screen protection on all from every camera maker out there seems to be very, very good.
If I was heading for particularly rough environments (e.g., Baja, northern Sahel/sub-Saharan/Sahara regions, Petra/Jordan, Kingdom, etc., etc. - the fine sand is insidious and can't be avoided; it gets into everything) I'd install a GGS again because it fully seals to the outer edges of the rear LCD and prevents any and all dust, sand, grit and moisture from getting to the screen.
Back in the day, I used a number of cameras that gave it up completely in dry, sandy, hot regions - gritted up shutters; dials, controls, focus rings and aperture rings jammed/seized with grit, and so on). DSLRs and the latest lenses are no more resistant that the older pro and enthusiast gear, and I don't care what kind of Gorilla Glass the camera makers use. Wind blown, fine sand in 35C-40C is a relentless and nasty abrasive. But that's the only sort of environment in which I'd react protectively with a GGS screen protector.