Here’s some of my blogs that discuss our Exchange 2007 implementation:
Good luck in your upcoming implementation!
Our migration went smoothly. Once we had Exchange 2007 up and running with storage groups and mailboxes created then moving the mailboxes was easy. Using the Exchange 2007 console I could schedule batch moves at night and check them in the morning. I had no failures. Just make sure you have planned well before you start and set mailbox size limits ummediately if you have not done so previously.
We sorted users out according to size and made storage group limits, moving people into the appropriate storage group depending on their position or mailbox size needs for business reasons only.
For us we have a script we use for creating new users and made it so new users by default are not enabled for active sync. They are enabled by default if you create them through the exchange console. We then disabled all users for active sync and re-enabled only those who were allowed. We do not support anyone syncing with personal devices. They have to have a company phone or special permission to sync their personal device. We heard a lot of crying of course, but once the policy was established everyone fell in line.