“Even before last week’s sales of contemporary art at Christie’s and Sotheby’s in New York, the catalogs for those events indicated that art made during the last four decades has become attractive to potential buyers. And the sale results confirm the emergence of a cohort of youngish collectors eager to buy recent art at prices that continue to rise, sometimes to levels that astonish dealers. Concomitantly, interest in art that has yet to prove its historical staying power appears to be driving the market.”