According to ITWire SharePoint 2007 is going to be launched on November 30th, along with Vista.
Update: Nov 6, 2006, Microsoft announces that Office 2007 has been released to manufacture (RTM). This is milestone that marks the completion of the development and testing phase. According to their press release it will be available "worldwide" from November 30th.
However, it may be available earlier for companies that have access to the Microsoft software download sites. Certainly the MSDN Subscribers site has an announcement saying that it will be available 7 days from the RTM.