December 21, JFK: we stood behind an older couple (70s or so) at the ID station before security. I don't know about liquids but the woman was asking whether her round-tip cardboard nail file was legal while her husband dug in his bag for documents. Clearly very infrequent fliers. I wasn't surprised to see her taken aside for wanding and a carry-on search.
In October, also at JFK, there were plenty of folks caught short by the liquids ban. With the TSA folks watching I offered to carry a bottle of pricey perfume in my freedom baggie for the lady behind me, who was completely unaware of the new (two month old) restrictions. TSA didn't seem to care.