Steven Sinofsky, president of Microsoft's Windows division, made the announcement during the company's annual sales meeting, according to the Windows Team Blog. The company had already announced late October availability for the new operating system, but did not give a specific date until today.
The release date applies to new Windows 8 PCs and to upgrades, which will cost $40 through January 31 for users running Windows XP or later. No specific launch day hardware was mentioned, but Microsoft's Surface Windows RT tablet should be available around that time.
Microsoft still hasn't announced non-upgrade Windows 8 pricing for users who build their own PCs or want to run the OS on Mac hardware. There's been some chatter that Microsoft will sell a "System Builder" or OEM version of the OS, but not a standalone full retail version.
Windows 8 is a major overhaul, with a new Start screen optimized for touch screens and an app store for tablet-friendly "Metro-style" programs.