Hey there. I have question about Windows 7. Consider "Program X". What's the difference between the next two options: A) Running "Program X" in "Windows XP (SP3) Compatibility Mode" (right-click the program -> properties -> compatibility -> run this program as "Windows XP (SP3)") B) Running "Program X" in the new Windows 7 XP Mode Desktop Virtualization technology (which is basicly a virtual machine running XP SP3) Technically I'd really like to know what really happens in the OS when you use option "A" above to run a program. Can anyone enlight me or point me to some technical documention that explains this? Thanks a lot in advance!