For future releases or RHL, consider integrating RHN registration preferences with the installer, such that a new installation could result in automatic registration if desired. Integration with kickstart would be nice also.
Kickstart makes some sense. I'm trying to get less interactive stuff in the installer, and pushed to a 'first boot' environment we run that handles all the stuff that can go bad. So I would recommend any interactive portion occur in this environment, whenever the OS devel team has time to implement it.
Thats what first boot is for.