This is it. After confirming RTM date and timeframe fro General Availability, Microsoft has announced that Windows 8 will be available on October 26th, 2012.

This Steven Sinofsky, PM on Windows, which announced it.

http://windowsteamblog.com/windows/b/bloggingwindows/archive/2012/07/18/windows-8-will-be-available-on.aspx