Chapter 14. Upgrades and Migrations
According to Ferris Research, if Exchange Server were a stand-alone software business, it would be the ninth-largest software company in the world. It is a solid bet that a lot of existing Exchange customers will be looking to move to Exchange Server 2010.
Depending on the software, you may be used to in-place upgrades, where you have an existing version of the software on the computer, run the installer, and end up with the new version of the software. Some of the previous versions of Exchange have supported an in-place upgrade process for at least one previous version back, but the Exchange 2010 upgrade process doesn't.
There is no in-place upgrade path for organizations running either Exchange 2003 or Exchange ...