This post really sends mixed messages.
It says that renaming a domain is the best migration path, but there will never be a rename tool for exchange 2007. Migrating to a new forest is a much more complicated process than a rename, but it looks like we are being forced in that direction.
In the last section ("Resolve two problems at one time") you say that the best option is to remove exchange 2007 and then rename the domain, but in the top part of the post you say "you cannot perform a domain rename even if Exchange 2007 servers are removed from the organization". And if you remove exchange 2007 where does all the mail box data go?
Basically we have all waited a month just to find out we can now install SP1 but that is just delaying the inevitable migration that we have all feared. Why can't we get a rename tool for 2007 to make our lives easier?