On February 26, 2011, Microsoft released an update to USMT 4.0, adding support for Office 2010 as well as fixing a few other issues.
You can download the update from: Information about the User State Migration Tool (USMT) 4.0 update
If using ConfigMgr 2007 and MDT 2010 Zero Touch you need to update one of the MDT scripts, read more on this blog archive: Michael Niehaus blog
/ Johan