I have just upgraded our live configuration to OnTime 2008, after much testing.
What we didn't test, was the Remote Server. This now seems to be a lot slower for Windows clients who are connected over the internet.
The web client is much faster at selecting a project on the tree, about 1 to 2 seconds delay versus 5 to 10 seconds.
On the server where the Remote Server is running, the CPU usage goes to 100% after a selection is made from the Windows client.
It seems that the main culprit is the w3wp.exe Network Service.
We do have multiple application pools and could potentially remove some of them. This however, wasn't a problem with Version 2007.
The server OS is Windows Server 2003 Web Edition SP1.