Hereabouts, among the young, I understand that the new(-ish) and relatively precise term for the genre of performance that most of us old folks hate, that most-self-indulgent and self-pitying kind of adolescent "singer-songwriter" crap, is "EMO." For "emotional," I assume.

Whatever "acoustic rock" may be, I would like to stipulate that it's not exactly the same thing as "folk rock." The former is defined by sound, the latter by lyrical content and attitude.

James Taylor performing a Marvin Gaye song, for example, is acoustic rock. Maybe even Tom Rush doing Chuck Berry and Bo Diddly, as he did way back in 1964 or so on his first LP. More recent examples are of course too numerous to mention

The Byrds and the Grateful Dead are folk rock, though perhaps not for every song they do. (The Dead would occasionally perform "unplugged" and thus qualify as Acoustic Rock as well, but their usual instrumentation and approach was highly electrified and "non-acoustic," while their songwriting, on the other hand, was always deeply rooted in American folk traditions.)