Joe Isuzu was the character from a famous series of advertisements in the late 80's. It featured a send-up of the stereotypical car/snake-oil salesman - the actor David Leisure played a smarmy guy who claimed that the Isuzu he sold had gin-u-wine llama-skin leather and 'enough cargo room to carry Texas'. The ads got more and more outlandish as they went along, and featured (relatively speaking) high-quality jokes. The series won acclaim and industry awards, and Isuzu sales damn near doubled.

Here's the funny part, though - the ad put Isuzu sales through the roof without ever mentioning any feature of the truck itself. It was a complete mind-job, not unlike the salesman it parodied. It was successful by taking a part of the 60s and making that part work for the advertisement. But instead of co-opting various 60s music or dress, the ad co-opted a very important part of the 60s youth culture - the use of irony to poke fun at the middle-class and show what's wrong with culture. See Kesey, Pynchon, et. al. for this. The tactic of irony (seen in TV before, but never with such success) in the commercial made the viewers (who invariably agreed that lying car salesmen were, in fact, bad) feel 'cool' and superior (to who?) for getting the joke, and improved the image of the Isuzu Corporation as people cool enough to make fun of themselves.

Unfortunately, the Isuzu Corporation didn't suddenly get taken over by a wave of 60s idealism, Isuzu trucks still sucked, and the whole point behind irony was made moot. Since then, irony has made massive inroads into American advertisements and, by extension, American culture. And since 'the system' was now using irony to its own ends, it lost all of the meaning it may have once had. Irony was no longer a way of holding a mirror up to the culture, to diagnose problems (and since irony never provided answers, it never worked that great anyway); it became what's wrong with culture itself.

For a deeper and much more elegant explanation, see David Foster Wallace.