Sinofsky's product development duties effective immediately fall to Microsoft Vice President Julie Larson-Green who worked under the former Windows boss. Larson-Green inherits responsibility for Windows at a time when Microsoft is transitioning to the so-called post-PC era where your desktop, tablet, television, and smartphone are all tied together via online services.
[Read: Text of Steve Ballmer's letter about Steven Sinofsky departure]
It's too early to blame Sinofsky's departure on a poor reaction to Microsoft's products as Windows 8 was released to the public less than three weeks ago. Despite a tepid reaction to Surface RT and an uncertain future for Windows, most critics believe the end of Sinofsky's tenure was largely a result of political infighting.
Sinofsky in a letter to employees--as published on Paul Thurrot's Supersite for Windows--said his departure was "a personal and private choice." Microsoft says Sinofsky's exit was a mutual decision between the former Windows head and the company.
Nevertheless, many reports claim that Sinofsky was a divisive and uncooperative figure inside Microsoft, which may have ultimately caused his undoing.
Microsoft has a reputation for being a loose collection of warring fiefdoms; however, the company is increasingly focused on inter-departmental cooperation and product integration. "Our overall business strategy [is] to provide integrated product and service offerings, and this requires deeper cross-organization collaboration," Microsoft said in a recent proxy statement to the Securities and Exchange Commission.