With the new Microsoft KMS service built into office 2010 you must run the following executable before you can capture your image.
C:\Program Files\Common Files\Microsoft Shared\OfficeSoftwareProtectionPlatform\OSPPREARM.EXE
The reason being is sysprep does not clear out the KMS identifier in Office like it does in Windows. So every machine will have the same identifier making it impossible for your KMS server to activate your Office 2010 clients. Run this executable before capturing your image and you should be fine.