7/18/2012
The latest tidbit is Windows 8's exact availability date is going to be October 26. (The last we heard at the Microsoft Partner Conference a week ago is it would be in "late October.")

October 26 will be the date Windows 8 will be available preloaded on new PCs and also to those purchasing it through one of the upgrade programs Microsoft has announced recently. Based on previous Microsoft statements, it also seems October 26 will be the date that Windows RT-based Surface PCs/tablets from Microsoft will be available via the Microsoft Stores and select online outlets.

Microsoft officials shared the exact date on July 18 with the thousands of Microsoft salespeople attending the Microsoft Global Exchange Conference in Atlanta, according to a July 18 post on the Windows team blog. (Update: I've added a photo of Microsoft Windows President Steven Sinofsky at MGX, about which one attendee of the conference tweeted and posted publicly today.)

Windows 8 is on track to be released to manufacturing by the first week of August, officials said last week. Windows Server 2012 and Visual Studio 2012 also will be released to manufacturing at the same time. But Windows Server 2012 won't be available to customers until September, Microsoft officials have said. Execs have declined to say when developers will be able to start using the final Visual Studio bits.

Microsoft officials said last week that business users with volume-licensing contracts will be able to get their hands on the final Windows 8 bits shortly after the product is released to manufacturing, which will be two-plus months before the product is generally available via retail. Microsoft officials are declining to say when those with MSDN and TechNet subscriptions will be able to obtain the final Windows 8 bits.

Microsoft officials have said those upgrading from Windows XP, Windows Vista, Windows 7 and the Windows 8 Release Preview will be able to buy upgrade copies of Windows 8 for $40 each. Microsoft officials have not said how much the promised System Builder SKU will be for those who want to build their own PCs. They also have not said whether a full, non-upgrade version will be available via retail and how much it will cost. But the unofficial word is Microsoft may be dropping full packaged product at retail with Windows 8.

Source: http://www.zdnet.com/windows-8s-delivery-date-october-26-7000001158/