Whatever happened to the literary avant garde?

Robert McCrum on the decline of an artistic movement
1950s French couple kissing in Paris.
Robert McCrum has written a short article for The Guardian's online website, mourning the loss of the literary avant garde:
Half a century ago, when Waiting for Godot was the succès d'estime of 1950s Paris and London, Beckett was certainly avant garde, as was his disciple, Harold Pinter. In the UK, next to these innovators, there was the translated work of Alain Robbe-Grillet, and Fernando Arrabal, author of The Burial of the Sardine. And from the US there was William Burroughs, and the heirs to the Beat generation. You never had to go far in a bookshop to bump into the avant garde, and some publishers – Calder & Boyars, for instance – even made a living out of it (though the less said about their methods the better). From roughly 1950 to 1980, the avant garde was alive and well.

But now what? Nothing to speak of, really. The most surreal news from the world of books is the trade press report that The Lost Symbol, Dan Brown's follow-up to The Da Vinci Code, is going to be launched in September from Random House with the biggest ever global first print run (some 6.5m copies) in the publisher's history.