very interesting post on desktop virtualisation on techworld - basically microsoft is partnering with citrix to redeploy what's fundamentally thin clientstyle computing as we know and love from the nineties.
In essence a lot of the compute is moved back onto servers and there's some tweaks this time to improve graphics performance.
Interestingly it's not a softgrid type environment where all the clients host a minimal operating system and execution engine and run virtual machines - the vmware style of solution.
This latter model means that execution happens locally and you can maintain a relatively close coupling between the user and the processes being executed - and all you need is a cheap device on the desktop and a deployment mechanism.
VmWare are working on this. Microsoft have their virtual pc and softgrid, not to mention sms, so why the return to thin client?