It appears to be only a matter of time before Apple (NASDAQ: AAPL) iTunes becomes the No.1 source of digital music.

For now, being No.2 will have to do. According to NPD data picked up by Reuters "Apple Inc’s iTunes digital media store has become the second-largest U.S. music retailer, behind Wal-Mart Stores (NYSE:WMT)."

iTunes has over 50 million customers.

Douglas A. McIntyre