Here's more fodder for those who argue that a large number of consumers still want physical media: vinyl sales at Amazon are up 745 percent from five years ago, the company said this morning. "Vinyl is the fastest growing music medium on Amazon," the company stated.

Amazon also said that vinyl is the most popular medium within AutoRip, the feature that provides customers with free MP3 copies of select vinyl albums or CDs they purchase from the online store. Amazon's reported growth in vinyl sales is consistent with an industrywide trend. Nielsen SoundScan estimates that vinyl unit sales will grow to 5.5 million in 2013.

Vinyl sales is still only two percent of overall market If that figure doesn't sound very big to you, it's because it's not. The Recording Industry Association of America says that it too saw a sales spike in 2012 of 29 percent, but that the figure still only represented 2 percent of the overall market. One reason that vinyl might be making up a larger share of music sales at Amazon is the decline of the other formats. Download sales are soft and the CD is headed for obscurity. Most in the music industry say what's hurting downloads is the rise of subscription music services, such as Spotify and Rdio, and web radio services like Pandora. Unlike a growing number of competitors in the online music area, Amazon hasn't branched into subscription or web radio in any significant way. Regardless, vinyl remains the preferred format for a niche group.