Industry analysts have called on Microsoft to provide facts over fiction over claims Office 365 is flying off the shelves.

Believing suggestions that 25% of enterprises are currently using Office 365 to be wide of the mark, Gartner analyst Michael Silver questioned the figures.

"It's a big claim to say 25% of enterprises are using Office 365," Silver told IT News.

"It would be nice if Microsoft gave more detail because one out of four customers haven't moved to Office 365 to a large extent."

Fresh from positing encouraging quarterly results, based on "bold bets" on cloud services, Microsoft CEO Steve Ballmer will no doubt beg to differ.

"The bold bets we made on cloud services are paying off as people increasingly choose Microsoft services including Office 365, Windows Azure, Xbox LIVE, and Skype," he said last week.

Chief operating officer Kevin Turner also backed up the claims, saying: "Our enterprise business continues to thrive."

But strong statements from strong figures within the company still carry little weight without solid factual support, as argued by Silver.

"What you're seeing is probably a lot of trials," he said. "It's hard to tell what that number means."

In early March TechDay reported that cost-cutting customers are threatening Microsoft’s licensing revenue, sticking with their perpetual licenses despite Microsoft’s new releases.

This is especially evident in business, with companies commonly skipping Office’s typical three-year cycles while migrating systems as it can take years to roll out an edition.

“The world of work is changing extremely fast," Microsoft's Asia Pacific Marketing and Operations head Todd Cione told TechDay.

“Microsoft Office 365 is explicitly designed for this rapidly changing and evolving world of work.

“We now have more alignment with the biggest trends than before, covering social, big data, mobile and cloud.”

This may well be the case, but until the claims are backed with hard facts - it frankly means very little.

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