On July 13th, 2010, support for Windows 2000 Server ends. Microsoft provides 10 years of support (5 years Mainstream Support and 5 years Extended Support) at the supported service pack level for most Business and Developer products. With support for Windows 2000 Server coming to an end, organizations need to start planning to migrate their Windows 2000 Server based infrastructure to later Windows Server family releases.
It’s mainly to promote the latest versions of windows server product like windows server 2003 and newly launched windows server 2008, if you are still using the windows 2000 then it’s a time to think and upgrade to newer versions before July 13th, 2010
For more info http://www.microsoft.com/windowsserver2008/en/us/why-upgrade-2000.aspx
