I wanted to make sure all TFS users adopting 2010 saw this -
This morning TFS released the GDR patch for TFS 2005 users who want to connect to a TFS 2010 server.
You can find more info about the patch here:
The drive for developing this patch was entirely your user feedback. After long debate, we originally decided to ship only a patch to get a great experience connecting 2008 clients to the TFS 2010 server. However, you guys told us loud and clear you needed 2005 as well. :) Thanks for the feedback. Here is the link to that 2008 compat patch as well, for convenience. :)