Do you hear "snarky", to imply some level of wry, off-the-cuff, perhaps mildly acerbic, humor?

People I know use the word that way, but most online definitions put it, I'd say more in the range between acerbic and acid, with no humor. MW does have a second "irreverent" sense, that's also pretty good for how I have it, but if that's not the common interpretation I'd better make some changes...

My impression is that people use snarky to mean everything from "mean-spirited" or "rude" (no hint of humor) to "sarcastic" (humor with a hostile edge). I don't associate the word with merely wry or off-the-cuff humor. But let's see how various reference works define the term.

From Merriam-Webster's Collegiate Dictionary, eleventh edition (2003):

snarky adj [dial. snark to annoy, perh(aps) alter(ation) of nark to irritate] (1906) 1 : CROTCHETY, SNAPPISH 2 : sarcastic, impertinent, or irreverent in tone or manner {snarky lyrics}

The Eleventh Edition's definition 2 is new to that edition. The Tenth Edition (1993) has only the "CROTCHETY, SNAPPISH" definition, and the Ninth Edition (1989) has no entry for snarky.

From The American Heritage Dictionary of the English Language, fourth edition (2000):

snarky adj Slang Irritable or short-tempered; irascible. [From dialectal snark, to nag, from snark, snork, to snore, snort, from Dutch or Low German snorken, of imitative origin.]

The third edition of the AHDEL has no entry for snarky.

From Barbara Kipfer & Robert Chapman, Dictionary of American Slang, fourth edition (2007):

snarky adj Irritable, touchy : She's just in a snarky mood, that's all [—Noel B B Gerson]/ a snarky, no-illusions, but far-from-hopeless comedy [—Ms magazine] [1906+; fr British dialect snark, "to fin fault, complain," fr the basic sense "snort, snore"; of echoic origin, with cognates in many Germanic languages]

The third edition of Kipfer & Chapman (1995) has the same entry for snarky as the fourth edition (except that it also identifies the sources of the two included examples).

A very different—and presumably obsolete—meaning appears in the first edition of the Dictionary of American Slang, however. From Harold Wentworth & Stuart Flexner, Dictionary of American Slang (1960):

snarky snorky adj. Elegant; ritzy. 1941: "It's a snarky one [automobile]—a super-dooper." Radio, Fibber McGee, Nov. 18. Dial.

Clearly, snarky is a rapidly evolving term, and dictionaries have only recently begun to come to grips with it. The second definition in the Eleventh Collegiate Dictionary and the second example in Kipfer & Chapman seem to support your suggestion that the word can refer to "mildly acerbic humor." But dictionaries haven't yet caught up with the more benign sense of "wry [or] off-the-cuff" humor that you suggest—if indeed a significant number of users have that meaning in mind.

'Snorky' around here (Sussex,Uk) is a mild rebuke for someone who is being irascible and rude. It's a minor criticism. Nice word . Personally not heard 'snarky' variant for many years.