It seems to be official.
Microsoft’s Windows 8 will be available on October 26th 2012.
From the Windowsteamblog:
Just a few minutes ago, Steven Sinofsky announced at Microsoft’s annual sales meeting that customers will be able to get Windows 8 – whether in upgrade fashion or on a new PC – starting on October 26th. Earlier this month at the Microsoft Worldwide Partner Conference, Tami Reller told attendees Windows 8 would be available in October. But now everyone has a specific date to mark on their calendars. It’s on mine!