Apple now adding 500,000 new iTunes accounts per day

Deidiu plotted out Apple's previous milestones announced since 2009 to calculate its current growth rate. If Apple continues at this pace, it will add another 100 million accounts by the end of this year.

Earlier this month, a Morgan Stanley analyst noted that Apple's more than half of a billion iTunes accounts are driving new opportunities for growth, describing Apple's global number of accounts as second only to Facebook's billion, but more importantly generating more revenue per account than even mega-retailer Amazon.

That report also noted that Apple's account base was growing significantly faster than its peers, and those accounts were generating the highest free cash flow per account by a wide margin.

In April, NPD Group released figures giving iTunes a 63 percent share of the US digital music market, three times that of second place Amazon (at 22 percent), and in video downloads, a 67 percent share of TV shows and 65 percent of movies.

Amazon and Microsoft's Xbox were tied in second place for movies with 10 percent shares, and collectively shared a 22 percent slice of the TV downloads market. Google Play and other digital media download services didn't figure into the top 80 percent of any category.