I have a MSDN package and a Microsoft MVP. I am in on all of their Betas as well along with all of their developers packages. I am also in their private newsgroups which are only for MVP's and developers to discuss such things.
The MVPs are some of hte first to test this software right from the developers since we have direct chats with them weekly. I am not saying your friend is a liar but i find it hard to believe that he got something that is not mentioned even among the DX developers at M$.
I have been keeping a eye on that newsgroup and have had the talks with the developers to see if they really were gonna port DX10 back to XP. I have not seen nor heard anything about this. And on my Connect page i am a DX Beta tester as well. I dont have it. Which would make me mad that other have and i havent.
That is a shot of me viewing the newsgroups. As you see it says private. I had to cut out all the stuff cause NDA stops me from showing all the info. But i can say that no DX10 for XP was mentioned in those topics.
AMD you wonder why your Vista Ultimate is slow. You are using a old hacked version of Vista. Try getting a better one.