The Mainstream support for 2007 versions of Office, SharePoint, and related products, will end on Oct. 9, 2012.

The current support life-cycle dates for Microsoft SharePoint 2007 server, can be found in the following page:
Microsoft Support Lifecycle
http://support.microsoft.com/lifecycle/?LN=en-us&p1=11373&x=14&y=14

The current support life-cycle dates for Microsoft products in general, can be found in the following page:
Support Lifecycle Index
http://support.microsoft.com/gp/LifeSelectIndex