Virtual desktops have been around for decades. I used them in the '90's on Solaris Openlook and HP-UX VUE before they moved to CDE. VMware 1.0 was released in 1999, and I had production VM's the next year. Just goes to show, if you want to see what Microsoft will be working on next, look at what Unix/Linux was doing 10-20 years ago.