That was the year that the iTunes Music store revolutionized digital music, but as the number of music streaming and internet radio services continues to grow, is a second digital music revolution on the horizon? The latest quarterly Nielsen SoundScan report shows that sales of individual digital music tracks in the US fell 5.7% from 1.24 billion to 1.26 billion and sales of whole albums (usually more robust and less likely to fluctuate) also fell by 0.1%. According to Billboard, the music industry believes that this drop in sales is due to the growing popularity of streaming, which is starting to slowly cannibalize digital sales, and the trend is set to continue into the new year. YouTube is getting ready to launch a music and music video streaming service and Apple is widely expected to expand its iTunes Radio offering beyond the US in 2014.