Apple may be facing a second consecutive quarter of decline in Mac sales as gauged year-over-year, Piper Jaffray's Gene Munster suggests. The analyst cites new statistics from NPD Group, which show that April shipments fell 1.8 percent versus the same period in 2008. Although not as harsh as the 5 to 10 percent initially called for by Piper, the drop could foretell substantial problems with the
