DirectX 10.1 Won't Require New Hardware
But you might want it though
http://www.xbitlabs.com/news/video/display/20070815123340.html
There have been quite a few rumors on forums over the
past week that DirectX 10.1 will require users to purchase a new DX10 hardware.
Obviously this rumor got many people upset and got some people to believe they
will have to purchase another piece of hardware to use with Vista.
During a recent interview with Next-gen, Microsoft stated:
"DirectX 10.1 fully supports DirectX 10 hardware. No hardware support is being removed. It's strictly a superset. It's basically an update to DirectX 10 that extends the hardware functionality slightly."
There will be some new features with 10.1, so if you want those abilities, then you will need the new hardware. However, there is no need to upgrade your current setup otherwise.