A few hours ago (one hour later than expected, at 4.00 PM PDT), Day of Defeat: Source was released in the wild. This is the first product from Valve that benefits from the HDR technology. The Valve engineers went to interesting challenges to make HDR work on both ATI and NVIDIA cards, as described in this ArsTechnica article (and another link here).

I took a quick look at the game a few hours ago, and it looked great. However, right now I cannot play it apparently:

Well, maybe another day...