Check out the following:
http://www.microsoft.com/windows2000/server/evaluation/news/bulletins/extend
edsupport.mspx
Exerpt from that page:
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Overview
. On June 30, 2005, the Windows 2000 product family enters the
Extended Support phase, which continues for at least 5 years through June
2010.
. Microsoft offers a minimum of 10 years' support (5 years Mainstream
plus 5 years Extended) for business and developer products. The Microsoft
support life-cycle policy provides predictable coverage of Microsoft
products and continues to set the standard for product support policies
industry-wide.
. Microsoft is not ending support for Windows 2000. During the
Extended Support phase, Microsoft continues to provide security hot fixes
and paid support but no longer provides complimentary support options,
design change requests, and non-security hotfixes.*
Note: The Update Rollup for Windows 2000 Service Pack 4 (SP4) is the final
release of Windows 2000.
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And also
http://support.microsoft.com/lifecycle/ (referred to in the exerpt
above)
The levels of support have changed, but MS is still supporting 2000.