As expected the Windows 8 tablet will go on sale along with Microsoft's revamped cross-platform operating system. It is the ARM-based Surface RT which will go on sale in October with the Surface Pro due around 90 days later, so early in 2013. See also: Microsoft Surface RT vs Apple iPad comparison review.
"The next version of our operating system, Windows 8, will be generally available on October 26, 2012. At that time, we will begin selling the Surface, a series of Microsoft-designed and manufactured hardware devices," Microsoft said in its annual report, according to CNET.
More details: Microsoft surface specs, pictures, video.
So we have a date for the Surface RT but unfortunately Microsoft hasn't revealed any pricing for the tablet or the Pro version.
"Suggested retail pricing will be announced closer to availability and is expected to be competitive with a comparable ARM tablet or Intel Ultrabook-class PC," said Microsoft.