On April 28, Apple's iTunes digital music service turned one year old, celebrating sales of 70 million tracks -- not too shabby, baby! While the buck-a-song downloading outfit still claims only about 1.2 percent of the U.S. music market, iTunes' impressive receipts -- once an impossible dream in the Napster free-for-all era -- are having a positive effect on more than just Apple's bottom line. Not only are first-quarter iPod sales up a staggering 909 percent from the same period last year, but the digital boom has also revived the dwindling singles market, outselling retail units 12 -- 1 (surprise! OutKast's ubiquitous ''Hey Ya!'' was year one's top-selling download). More good news for the recording industry: CD album sales are up eight percent after years of decline. What a revelation -- it takes people actually paying for music to finally turn the biz around.