Financial analysts covering Microsoft seemed to be most concerned about how the shifting PC market would affect future sales of Windows, to judge from the questions they asked during an investor teleconference call held after the release of the financial results. How will the proliferation of new form factors for computers -- tablets, convertibles, all-in-ones -- alter the usually predictable sales of the Windows OS?

Microsoft positioned Windows 8 as an OS that can encompass this wider market. This OS, unlike competitors such as iOS and Android, can offer a single unifying experience across different devices.

"The exciting thing about Windows 8 is that it really redefines what people think about devices, and how they think about devices," Klein responded. "Up until now, [customers] have been forced to choose between PCs and tablets, and make trade-offs of what they get. With Windows 8, you can get whatever you want at whatever price you want."

The adoption process of Windows should continue unabated, Klein said. Enterprise rollouts are steady, and Windows XP will reach end of life in a year-and-a-half, which will spur demand for the new OS.

The weakening demand for Windows over the past three months was due to a number of seasonal and situational factors, Klein explained. OEMs spent the past quarter letting their stock of Windows 7 machines dwindle in anticipation of new Windows 8 machines. Economic sluggishness around the globe -- and in Europe in particular -- slowed sales as well.