I think you got a decent deal. One thing about direct x 10 that seems to always be lost is that most at least IMO of the new eye candy things that are supposed to go along with DX10 can be accomplished on DX9 hardware with great coding. I only have one example but look at most of the Crysis vids. Most if not all, excluding the newest one which could possibly be running on DX10 hardware, are all running on DX9 hardware. And you still get the stunning graphics. Yes the new 8800gtx will spit out huge FPS on every current game save for oblivion which it still kicks ass at, but other than the internal changes being made current hardware excluding the 8800gtx can run the upcoming games looking just as good (not at super high res but thats what the new GPU's are for) if the games are coded well. Take for example the movie Toy Story it was all rendered on hardware over 10 years old now but it still made amazing looking graphics, could that have been done real time no but that is proof that changes in DX whatever are not really all that important it is more important that the GPU's are getting more powerful able to render higher quality stuff real time and the game makers are able to come up with better looking visuals.
IMO DX10 is not some huge revolution that is going to change the way games are played or whatever you want to say. It is a tiny tiny player in the progression of game and graphic possibilities. What always must be remembered is that it is the game maker who will make a better looking game not microsoft. (I don't include aTI and nVidia since they make the hardware to produce what the game maker envisions)