It's an understatement to say this is a big deal.
When Microsoft launched the Surface tablet, its first attempt at a PC, CEO Steve Ballmer said, "Windows is the heart and soul of Microsoft from Windows PCs to Windows Servers to Windows Phones and Windows Azure."
The man who has been in charge of the heart and soul of Microsoft is out of the company, reportedly because he clashed with other top executives.
If it sounds familiar it's because Apple just fired Scott Forstall, the man who lead iOS, which is arguably the heart and soul of Apple. Forstall was pushed out because he didn't get along with Apple's top executives.
Where the comparison falls apart, however, is when you think about how important each executive is to his company.
Without question, Forstall was a talented, valuable executive. But his signature achievement, the construction of iOS, has a giant asterisk next to it because of Steve Jobs. Jobs' name is the first on the patent for the iPhone software. Then Forstall. Jobs was the leader at Apple, not Forstall.
At Microsoft, it's a much different story.
Sinofsky has led Microsoft's Windows division for years now, and no one would say he's leaning on Steve Ballmer for his success.
Sinofsky was Bill Gates right hand man in the 90s. He warned Gates of the coming importance of the Internet. He later took over the Office division, whipping it into shape. From Office, he moved to Windows.
Sinofsky took over after the company released Vista, a widely panned operating system. He led the development of Windows 7, and delivered it to critical acclaim on time. Now he's delivered Windows 8, a completely redesigned operating system.
As Sinofsky gained power within Microsoft, he reorganized Windows in his own vision. He cut out middle managers. He started to gain influence over other divisions.
He was rumored to be the next CEO. And that may have been what did him in. We're hearing he asked for a formal nod that he was next in line for the throne.
Ballmer balked, and now, Sinofsky's gone. And that means someone else is either going to have to work within the structure he built, or clean it out and figure out a new structure.
Microsoft is actually splitting up his role, giving it to Julie Larson-Green and Tami Reller. Larson-Green will be leading the engineering and Reller will take over the business.
This is the best and worst time for Microsoft to undergo a massive executive shake up.
It's good because it just launched Windows 8. Whatever the plan is for the next version of Windows is probably in the early stages.
It's terrible because Apple and Google are eating Microsoft's lunch.
Just five years ago Microsoft was the world's leading personal computing company. Today, the rise of Android and iOS have made it much less powerful.
These new executives are going to have to come up with a vision for Microsoft to compete with iOS and Android. And when once they've done that, they're going to have to execute against that vision. That means delivering strong software on time, something Sinofsky did over and over again.
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