I recently upgraded from exchange 2007 to 2010. I followed a nice easy to use upgrade guide found here: http://technet.microsoft.com/en-us/exdeploy2010/default.aspx#Home .
So you might be wondering why upgrade to Exchange 2010? On the surface it looks awfully similar to Exchange 2007 but comes packed with some nice new features. The following are some of the features I like best.
Online Mailbox Move– You can now move mailboxes during business hours without any interruption to the users.
Database Availability Groups – You can now have up to 16 Mailbox servers that host a set of databases and provide automatic database-level recovery from failures that affect individual servers or databases.
Archiving – You can now preserve email data with archiving policies while seamlessly giving users access to the through either Outlook or Outlook Wepp App.