US Mac sales were up 35 percent year-over-year in May, according to new data from the NPD Group. The number compares with 39 percent in April, and Piper Jaffray analyst Gene Munster suggests that for the whole of Apple's third quarter, Macs may grow 19 to 23 percent versus the same period in 2009. This would represent between 3.1 and 3.2 million computers sold.
