We were also shown a neat Ruby Demo running on DirectX 10:

9 ATi Radeon 2000 Series Launch: X2900XT Review

10 ATi Radeon 2000 Series Launch: X2900XT Review

11 ATi Radeon 2000 Series Launch: X2900XT Review

Then later, another DirectX 10 demo, this time a new upcoming
game called Call of Juarez:

18 ATi Radeon 2000 Series Launch: X2900XT Review

19 ATi Radeon 2000 Series Launch: X2900XT Review

Below, you see how different the game looks running DirectX 9
vs DirectX 10:

15 ATi Radeon 2000 Series Launch: X2900XT Review

14 ATi Radeon 2000 Series Launch: X2900XT Review

The most obvious difference is seen when looking at the much
better-looking water effects, and High Dynamic Range effects.