Now that he's been given the keys to the Microsoft car, it's up to Nadella to prove that he can drive it faster than Ballmer, and down some new roads.
He'll have a part-time co-pilot in co-founder Bill Gates, who is stepping down as board chairman to take on a role as technology advisor. In a video released Tuesday, Gates said he will devote one-third of his work time to Microsoft, more than he has been devoting to the company in recent years.
For now, there are some areas that clearly will require close attention from Nadella, including Windows 8, which needs further refinement; the Surface tablet, still a work in progress; the upcoming integration of Nokia's smartphone business; and the nagging displeasure of longtime investors peeved at the company's stagnant stock price.
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