Here is an interesting tidbit and a rare kudo to MS. When you setup a TS roaming profile for users who connect to server 2003 TS boxes and then start introducting 2008 TS serversas well you will not need to make any changes to your TS profiles. By default when they connect to the 2008 box, it will create a TS profile in the same directory as your TS profiles regularly are and append the 2008 profile with a V2. For example if your TS profile path is \\server1\users\userA, it will create a new folder \\server1\users\UserA v2. From then on in it will auto sense the TS server they are logging into and user userA for the 2003 TS box and userA v2 for the 2008 TS box.
Pretty cool stuff.