Originally Posted by
Felix Saddler
Also when is DX10 available?
DX10 is an integral part of Vista and, I believe, will not be issued in an XP-compatible format. It is also not backwards-compatible with DX9, so many DX9 (and older) games will not run on DX10. A version of DX9 will be included in Vista to allow older games to run.
There is a short technical explanation of DX10
here which helps to explain why MSFSX is so much better in DX10 than in DX9 - and the CPU overhead should be lower! At least I now know I'll be getting Vista when it comes out!