But how the heck does the canon become established in pop music? The awarding of prizes and certificates by institutions, such as the Grammy awards, is fraught with influence and non-aesthetic criteria. The Rock and Roll Hall of Fame seems to have a bit wider vision, however there are questions about the nomination process which is apparently controlled by a few individuals not themselves musicians. Some of the traditional mechanisms found in the classical world, such as the selection of particular works for performance by orchestras, chamber groups and soloists, seem almost irrelevant in the pop music world. The 'work' itself is the original recording and not a score that others perform. There are instances of musical groups performing a whole album that is considered 'classic', but in the larger scheme of things, these are not very significant. Some songs become canonical by being covered by numerous other artists, such as "Yesterday" which has had reportedly over 2,500 cover versions. Others, like some of the songs of early blues musician Robert Johnson, have had fewer, but more influential covers. The case of Robert Johnson is more analogous to the posthumous career of a classical composer.
We may be forced to look at record sales over long periods of time to get a sense of the importance of a particular popular musical group. If we look at the Wikipedia page on best-selling music artists we find tied at the top of the list the Beatles and Elvis Presley with perhaps a billion sales each. Since these numbers were racked up over a fifty to sixty year period that indeed tells us something. But not necessarily! The late quartets of Beethoven, now recognized to be some of the greatest music ever written, saw very few performances over the first hundred years of their existence. For example, one scholar has collected evidence that in the twenty-five years after Beethoven's death, his home town Vienna--a great musical center--only saw a total of seven performances of any of the late quartets. The Great Fugue was only performed fourteen times in all of Europe in the fifty years after his death. So record sales, analogous to performances, may only obscure the relative quality of musical artists in the pop world.
Now I don't have any answers to these questions except the bromide: only time will tell! But I thought it was worthwhile just musing about it. Let's end with a selection from #27 on Rolling Stone's list of the greatest albums of all time:
UPDATE: I seem to have left out any mention of the influence of historians and theorists on canon formation. I actually pay a fair amount of attention to them. For example, one indicator of the importance of the Beatles is the attention paid to them by music theorists. Walter Everett took two volumes to cover all the songs of the Beatles and, except for a predilection to Shenkerian analysis, they are very well done. The sheer number and quality of books on the Beatles is itself a strong indicator of their importance. As for historians, ones that specialize in popular music are still relatively few and the enormous growth in pop music in the last 50 years has yet to be fully understood.