Last nite saved me a good long week of work.
Active Directory Domain Rename (RenDom.Exe) works like expected. Manual intervention is only with software that store user credentials in pair with host information, as Backup Exec does and client domain pointers that are left intact, pointing to no-longer-existent hosts. Besides the very long task list, the effort of restarting all machines, but keeping all settings, security, profiles, etc, was a big SMILE in the middle of the nite. Even all the DNS records change on the fly, and you can rename whole trees, parts of your dc-structure, and distinguish between netbios and full resolv.
Time for a cake! & later on to more productive issues, as moving things to new hardware, better structuring of services, smtp redundancy etc.
Kind regards / Peter