“A sea change in the art market was stunningly apparent last night at Christie’s sale of Impressionist and Modern art, where most of the buyers spending millions of dollars on everything from stark Giacometti sculptures to dreamy Signac landscapes were mainly Europeans taking advantage of the weak dollar. While the prices may have seemed high to the Americans in Christie’s packed salesroom at Rockefeller Center, the successful European bidders acted as if they were getting bargains.”