Exchange 2003 SP2: Migrate or Wait?

Timing is everything, whether you're ballroom dancing, skeet shooting, or deciding when to upgrade your Exchange Server environment. Many organizations that have resisted upgrading or migrating to Exchange Server 2003 are reconsidering now that mainstream support for Exchange 2000 Server and extended support for Exchange Server 5.5 have ended. But with the next version of Exchange, code-named Exchange 12, looming on the horizon, is migrating to Exchange 2003 Service Pack 2 (SP2) worth the time and effort? Let's consider your options.

Your Options, Pro and Con
Microsoft uses two terms to describe moving between different versions of Exchange. A migration is the process of moving from Exchange 5.5 to Exchange 2003 or Exchange 2000. An upgrade is the process of moving from Exchange 2000 to Exchange 2003, a fairly simple process. For this article I'm going to follow this usage instead of lumping the two terms together. The big difference between these two processes involves changes required to the underlying OS and directory architecture. . . .