The strategy of offering Office 365 at a discount and pushing that rather than a perpetual license could be an even bigger boon to Microsoft as tablets replace PCs, Miller argued. That relies on several assumptions: That people buy new tablets more frequently than they once did PCs, and that Office 365 is a requirement for Microsoft's suite on non-Windows tablets, such as Apple's iPad and those powered by Google's Android. Office 365's ability to assign Office to any of five household devices, then reassign them later to new, replacement PCs or tablets, may prove to be its strongest selling point as consumers, in Miller's words, "rotate out" new hardware for old.
But there are as many, if not more, unknowns than knowns.
"I think this point-of-purchase mechanism will result in subscriptions, at least for Year One," said Miller. "The question is, what does retention/churn look like at the annual renewal? We'll have to wait and see."
Gregg Keizer covers Microsoft, security issues, Apple, Web browsers and general technology breaking news for Computerworld. Follow Gregg on Twitter at @gkeizer, on Google+ or subscribe to Gregg's RSS feed. His email address is email@example.com.
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