"There's a fair amount of new stuff in Windows 8.1, including support for Miracast and Wi-Fi Direct printing," said Miller, citing two examples of the new features that hardware makers will want to support.
Moorhead agreed that the two months won't be wasted, but are needed by hardware makers to conduct testing of the update on old and new devices. "Consumers will expect 8.1 to work flawlessly on all those platforms," he said. Minus that testing — if, say, Microsoft had offered Windows 8.1 to all current Windows 8 device owners right after RTM —OEMs might have been flooded with support calls if glitches surfaced.
OEMs would have mentioned those concerns to Microsoft. And with the bulk of Windows licenses sold to computer makers, not direct to customers for in-place upgrades, Microsoft would be sure to listen.
Moorhead also cited Microsoft's reluctance to give some OEMs an advantage as another partner-related reason why it's withholding Windows 8.1.
"They want to keep a relatively even playing field among OEMs," said Moorhead. "Some could flip 8.1 quickly. System builders could have PCs ready almost instantly, but Microsoft has never wanted to give a huge advantage to one class. They especially don't want to put their big OEMs at a disadvantage."
There are other reasons, the experts added, that tip the scale toward later, not sooner.
"In any case, Microsoft will really want to do a lot of PR [between RTM and GA]," said Miller. "I think they're just trying to be conservative and keep focused on the fourth quarter."
One group that has typically had early access to a new version of Windows — developers and enterprise IT professionals — are waiting to hear how they'll be treated under the new regime.
Some veteran Microsoft watchers, such as ZDNet blogger Mary Jo Foley, have said their sources reported that MSDN (Microsoft Developer Network) and TechNet subscribers won't get Windows 8.1 before October.
If true, that would be a blunder. "That would be a mistake," Miller said. "They have to get it out there as soon as possible." Instead, said Miller, app developers should get an early look at Windows 8.1 final code so they can test their apps against the update and start work on revisions — and new apps — that take advantage of 8.1's new features and functionality.
Microsoft on Wednesday declined to comment on MSDN and TechNet subscriber access to Windows 8.1 RTM, but seemed to leave the door open when a spokeswoman said the company would "have more to share in the coming weeks."
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