In planning for your MOSS 2007 upgrade to SharePoint 2010 (SP2010), please realize that there really isn’t an upgrade per se. SP2010 is radically different under the covers so an in place upgrade is really a migration or conversion. However, before you roll your eyes in frustration, check out the article here for some great tips. I went to Ignite Training for SP2010 several months ago and the article linked about is a good reference about migrating your MOSS content databases (and if you must Shared Services Provider) to 2010. In a short statement – if you haven’t yet fallen in love and mastered PowerShell, now is the time! SP2010 PowerShell commands make it very easy and powerful to bring in your content DB.
I’ll be talking more about upgrades soon, but suffice to say – I’ve done it with lots of problematic databases (orphaned sites, etc) and the PowerShell script is a wonderful addition to the upgrade scenarios.