Taken from About.com/dance music/electronica's article "Billboard Dance Music Summit 2006 - Las Vegas Wrapup".
On page number 2:
...But what good is exposure if there are no sales? According to Tamara Conniff (Executive Editor/Associate Publisher - Billboard), over 60,000 CDs were released last year, with 40,000 of them selling less than 100 and only 100 selling more than a million. How are those odds? Digital downloads are clearly the answer for sales. Eddie Gordon (Music 2 Mix) predicted this on a DMS panel more than five years ago to an almost dismissive audience, stressing the importance of building a relationship with the audience and a database of everyone that buys your music. As head of Neo records, Eddie realized that if he knew who bought the first Darude single, he would have a better shot of selling them the second Darude single...