Leave the technologies aside: Which company is a more compelling stock buy than the other?
Smartphone market share
Beyond Wall Street, how do the companies stack up in the battle for tech users? Microsoft maintained an overwhelming lead in the desktop operating system business, keeping a roughly 92 percent share of the market from 2005 to 2009 (the last figures available from IDC). Mac OS X's share has varied between just 3.5 percent and 4.0 percent.
Apple took a significant lead in the smartphone race, capturing 15.7 percent of the worldwide market last year, compared with just 4.2 percent for Microsoft. However, both Gartner and IDC predict Microsoft's Windows Phone will beat out Apple's iOS for mobile market share by 2015, with Gartner expecting a 19.5 percent share for Microsoft and 17.2 percent for Apple.
In addition, Apple had a commanding 87.4 percent share of the worldwide tablet market last year, according to IDC. Gartner predicts Apple will keep a 69 percent share this year and will still have 47 percent by 2015. Windows doesn't show up in that forecast.
Bottom line: In one high-growth area, smartphones, several influential analysts believe Microsoft will eventually come out on top. In another, tablets, it's getting crushed. However, Microsoft has maintained its enormous lead on the desktop.