HMC 4.5 to Hosted Exchange 2010 SP2 Migration Guidance released
Microsoft recently released formalized guidance documentation and PowerShell scripts for migrating from HMC 4.5 (or non-HMC Exchange 2007 environments) to Exchange 2010 SP2.
implement.com is fully up to speed on the documentation and PowerShell scripts. We have already completed a couple of migrations as well. The migration itself has proven to be relatively straightforward, however, coexisting Exchange 2007 and Exchange 2010 SP2 on a hosting platform is complex and requires careful planning and testing. We have hit a few issues in testing that we have added to our internal "cook book" on how to do these projects as the TechNet based coexistence documentation doesn't fully cover the hosting scenario.
The blog announcing the migration guidance can be found here:
Released: Migrating Exchange from HMC 4.5 to Exchange Server 2010 SP2 whitepaper