With every release of Team Foundation Server, the installation instructions have changed; sometimes minor changes, sometimes major changes. In the December CTP, one major change is that Reporting Services is now installed on the application-tier computer. This means that dual-server deployment instructions have changed accordingly. As with any prerelease software, remember that the docs are constantly evolving with the bits. When installing Team Foundation Server, you would be wise to always review the Readme, Known Issues and Installation Guide to be aprised of changes to the process.