Bona fides: Nadella, 44, is an Indian-born engineer with degrees in electronics, computer science (from the University of WisconsinMilwaukee), and business administration (from the University of Chicago). Though he began his career at Sun, his highest-profile work has been at Microsoft, where he's worked since 1992. He is credited with launching BizTalk, Microsoft's Commerce Server, and Microsoft's Office Small Business products, but he's most famous for having overseen Microsoft's online initiatives.
Nadella helped transform Windows Live Search into Bing, and he oversaw Microsoft's other online businesses, including MSN, and their corresponding ad platforms. Nadella also convinced Yahoo to abandon its own search business and begin powering its pages with Bing. Nadella is currently the executive vice president of Microsoft's Cloud and Enterprise group, responsible for its cloud services, the platforms they run on, and the tools that build them.
Benefits: Nadella's current role brings a deep understanding of the cloud, the services it enables, the developers who write for it, and the ads that fund its operations. Nadella took a mere feature (Live Search) and turned it into the well-known Bing brand, capturing 29.3 percent of the U.S. search market between itself and Yahoo as of September, according to ComScore. Furthermore, Nadella has built out Bing with social data collected from Facebook, LinkedIn, and other social networks. In general, Nadella understands what needs to be done to power the "services" aspect of Microsoft's vision.
Baggage: Nadella's Online Services Division lost money like crazy. Yahoo has barely tolerated the ongoing Bing ad deal, and reportedly wants out. But instead of resolving its issues with Yahoo, Microsoft essentially promoted Nadella out of the way. And while Bing's search share has indeed improved, the improvement hasn't been huge: about 3 percentage points in two years. Taking on Google in search has been an almost insurmountable task, true. But if you're going to play, you have to play to win.
Perhaps even more significantly, Nadella has no chief executive experience. Handing him the reins of one of the world's largest tech companies would not be a market-inspiring choice.
Bona fides: Microsoft's chief operating officer, Kevin Turner, 49, has a management background, earning a business degree from a small university in Oklahoma. Turner then spent 20 years at retailing giant Wal-Mart, beginning as a cashier and ending as its chief information officer. In 2005, Microsoft hired him as COO, from which post Turner has overseen Microsoft's ad sales, sales and marketing, public relations, and other corporate functions. Turner also spearheaded Microsoft's retailing efforts, including the Microsoft Stores.
Benefits: Turner is Microsoft's version of Apple's Tim Cook during the Steve Jobs era: the man paid to make the trains run on time. Microsoft's net income has improved by 73 percent between fiscal 2006 (when Turner joined) and fiscal 2013, and revenue has increased by 76 percent in that period. You can count Turner among the data wonks who can be trusted to keep Microsoft's businesses operating smoothly.
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