He noted that Microsoft had already been changing its strategy, in part, with the arrival of Ozzie.

"If you could point to one thing Ozzie influenced, it is to become more aggressive and face up to this trend toward online services -- software as a service," he said. "Microsoft had, prior to Ozzie's arrival, certainly tracked that trend and flirted with it [on] different levels. But its general stance to software as a service and online services had been very measured and cautious -- in part because it has to worry about a new model such as that disrupting its traditional packaged software business model and its existing channel relationships.

"So Ozzie came in and, in short order, he was the driving force in getting Microsoft to come to terms [with] that software-as-a-service trend and to help fashion a strategy to pursue it in a way that won't be, at least in the near term, damaging or hurtful to the company," Davis said.

Michael Silver, an analyst at Gartner Inc., praised the choice of Ozzie to move into Gates' role. "We think Ray Ozzie is a good choice to reinvent the company to deal with competitive threats like Google," he said.

Laura DiDio, an analyst at Yankee Group Research Inc., said users likely won't see any near-term changes. But longer-term shifts at the company likely will be positive.