Just as a follow-up to the other question, all core technical content will be posted to the Exchange 2007 Technical Library on Technet, will be available in the CHM (help file on the DVD), and for certain conceptual material we will be making printable "guides" available for download.
The CHM will be on the DVD and accessible via download off the download center at the link I posted above. It will containt all of the content and will be updated every 6 weeks or so.
The printable guides will be built off of the conceptual material already posted to TechNet and in the CHM. The first of these will show up around RTM and our plan is to initially release planning/deploymnet guides for specific customers scenarios, such as migrating from E2K3 to E2K7. We will let the community know as these are available.