I found a D3DBook webpage on GDWiki. It is kind of site that is very helpful to programmers who are studying D3D10. Even though I haven't read it entirely, I'm sure that it helps programmers who have been using DX9 adapt to D3D10 easily.
Wolfgang Engel, well known as an author of game programming books, is a person of authors who joined to make the site. So the fact that he joined is enough to be worthy of attention because books that he wrote so far are very helpful.
I think most programmers might not have had any opportunity to use D3D10 at their project, because all of customers don’t have a graphic card that D3D10 is available. However, D3D10 have been being already used at development environment of XBOX360, and cheap graphic cards that support D3D10 will be spread more and more as time passed by. So I think game programmers have to get accustomed to use D3D10 to develop games that have greater graphic qualities than before and compete with other programmers in same area.
In fact, I didn’t also have the opportunity at my project, and I’m not used to D3D10. So lately I’m studying hard about D3D10 in order to be accustomed to handle D3D10. I guess most 3D programmers who are used to D3D9 can adapt to D3D10 easily if they study D3D10 a little bit.
http://wiki.gamedev.net/index.php/D3DBook:Book_Cover
