I just finished installing the Dec CTP of TFS.
I haven't tested the installation yet (that's the task du jour), but I am quite impressed with the installation. Concise instructions, well-written and well-formatted help. And (for me at least), no ugly and unexpected dialogs.
I installed on a VPC running Windows 2003 Server enterprise configured as a standalone AD / DNS server on its own local domain. My only issue was with SQL Server Surface Area configuration: I needed to expose TCP for communications. The pre-installation checks caught this and warned me before the TFS installation even started - which was really nice.
All in all, installation of the Dec CTP was a positive experience. Now, on to testing...
:{> Andy