For those who still haven't gotten their hands on the Windows 8 release-to-manufacturing bits via MSDN, TechNet, BizSpark, volume licensing or some other channel, Microsoft is making available via preorder the Windows 8 upgrade media as of October 12.

Those interested in obtaining a reserved, packaged DVD (or product key card version) of the Windows 8 Pro upgrade for $69.99 can place their orders via Amazon.com, Best Buy, Staples, Office Depot, the Microsoft Store and other retailers. Newegg is another outlet taking preorders , as my ZDNet colleage Ed Bott noted this morning.

Those looking to build their own PCs or install Windows 8 on a Mac are able to preorder a system builder/OEM license. As I blogged earlier this fall, the pricing for the system builder license is roughly the same as the cost of a Windows 7 system builder license . As Bott noted, the exact sysem builder pricing is $ 99.99 for Windows 8 and $139.99 for Windows 8 Pro .

As expected, there is no "fully packaged" Windows 8 product available at retail. If you want the equivalent, you have to buy an OEM/system builder license.

Current Windows users wanting to take advantage of Microsoft's previously revealed $39.99 upgrade price (which doesn't include DVD media) for Windows 8 still have to wait until October 26 to upgrade online via Windows.com. Users going that route will use the Windows 8 Upgrade Assistant in order to get their Windows 8 Pro copies. Most of those who have been testing Windows 8 are eligible to upgrade for $39.99 upgrade.

Customers who bought Windows 7 PCs as of June 2 and who want to upgrade to Windows 8 Pro for $14.99 also will have to wait until October 26 to redeem their upgrade offers.

It's not just the Windows 8 software that is available for preorder as of today. Several Windows OEMs, including Acer, Asus, Dell, HP, Samsung and Sony have started taking preorders for their PCs and tablets.

Microsoft still has not announced pricing or a preorder date for its Surface RT tablet/PCs. They will be available for purchase in Microsoft brick-and-mortar and pop-up stores , as well as select Microsoft online stores as of October 26.

One thing to remember if you're thinking about purchasing an ARM-based Windows RT PC or tablet, including the Microsoft Surface RT: Only certain mice, keyboards, printers and other peripherals which have been certified for Windows RT will work with these systems. Very few of Microsoft's own mice or keyboards are currently certified to work with Windows RT. I haven't found a list of third-party peripherals that are Windows RT-certified. Anyone else?