I have no idea what you're trying to link me to in your post, but here's the "now old" news regarding the first game to support Direct X 10:
http://www.gamershell.com/news/27536.html
As to your question regarding DirectX 9, Windows Vista Premium "Ready" performance (meaning having access to all the goodies) requires at least a DirectX 9 compatble GPU, so even Microsoft knows it can't expect every Sally and Tom PC buyer to have the latest and greatest. You're fine. DirectX is primarily backward compatible, so you'll just be missing some of the "Cry-goodies" by not having a DX10 compatible card.