If you're preparing yourself for Terminal Services in Server 2008, you should be aware that its new Session 0 isolation may change some application installations. Read this previous post, for more info on this change. It also changes the process whereby you connect into the console of your servers. Specifically, because session 0 is now reserved for the system alone, you can no longer connect to it interactively.

This changes the process whereby you connect to your server's console through the Remote Desktop Client. Previous clients used the /console switch for the connection. Now, with RDC v6.1 you'll want to use a new switch called /admin.

This switch instructs the RDC to locate the session ID number that relates to the console. As ID 0 is no longer interactive, another ID is managed by the system for console access (now called an "administrative session").

The change to this new command line switch shouldn't be a huge impact, but be aware that your processes may need to change if you currently use this switch to install applications or otherwise connect directly to consoles.

More information about the change can be found at: http://blogs.technet.com/askperf/archive/2008/01/04/mstsc-exe-no-more-console-switch-in-rdc-6-1.aspx