An MCSE does sort of expire in the sense that they are basically "master classes" in a particular environment, eventually that software is deprecated and the MSCE is no longer globally pertinent . However the skills used to get it are still valid in some ways, but they are usually heavily biased to a specific set. Since microsoft just improves and upgrades rather than replace, its still useful.
Who should take -
http://www.microsoft.com/traincert/mcp/mcse/mcse.asp
Requirements -
http://www.microsoft.com/traincert/m...quirements.asp