Sanfilippo said there was reason for customers to be concerned about the disparities between on-premise and cloud-based Exchange.
"Exchange 2013 was mostly about features for online and data centers, situations where someone was deploying large numbers of servers, hundreds of thousands of servers, that only a few clients would run into," Sanfilippo said. "It was not targeting or solving problems for on-premise."
That will likely continue, with features rolled out for Exchange Online long before they reach the on-premise editions. Clarke said as much today.
"Our development strategy continues to focus on Office 365 as the initial platform where we roll out new features," he confirmed. "This approach allows us to introduce and test new features at scale before including relevant functionality into on-premises updates."
Microsoft is using that first-to-cloud model elsewhere — it's said the same for the Office productivity suite, for instance — and will continue to use the tactic to entice customers to its services.
"It's part of Microsoft's move to a services business model," said Sanfilippo. "It's more stable, it's more under their control. It provides a lot of benefits to Microsoft."
Even so, Microsoft will continue to crank out on-premise Exchange.
"The reality is that not all [customers] will move to the cloud," Sanfilippo said. "Some are up against barriers, such as compliance and security concerns about data that they don't want to put up on Microsoft's servers. With the current way the cloud works, they have no option, so Microsoft has to continue [releasing on-premise Exchange] for the foreseeable future, at least for the next decade."
But he was surprised that Microsoft felt the need to come straight out and tell customers it wouldn't abandon the on-site software.
"Since this is coming from Perry Clarke, it's coming from high up on the Exchange team," Sanfilippo said. "They must have thought they had to quell some concerns and couldn't wait until next March." Sanfilippo was referring to the Microsoft Exchange Conference (MEC), which is slated to run from March 31 to April 2 in Austin, Tex.
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