According to figures released by Billboard.biz, Apple's iTunes store had vice-like grip on digital music sales in 2009, which further chipped away at brick-and-mortar shipments. Digital sales reportedly accounted for 35.5% of the industry in 2009, up from 31.6% 2008, while CDs and other physical formats comprised 49.3% of sales, falling from 57.5% in the year prior.

Apple's chunk of the digital market grew from 21.4% in 2008 to 26.7% last year, or about double it's 2007 share of 12.7%, making it the top music retailer in the US. Walmart followed with a 12.5% cut, falling from 15% in 2008. Similarly, Best Buy's digital share fell from 10.7% to 8.7%. Amazon grew in both digital and physical segments, with the former jumping from 4.9% to 7.1% and the latter from 4.2% to 5.8%.

Once touted as the industry's next big thing, mobile music sales flopped in 2009. Combined, Verizon, Sprint, T-Mobile, AT&T, and mobile content provider Zed represented a meager 4.9% of the market, down 1.7% on-year. Billboard attributed the decline to fading ringtone downloads as well as lower ringtone prices.