I have! Even if I do only have a lowly FX5900XT card to run it on. I've found the Neanderthal's football(soccer)fan club room, and the mutated plant, but the third secret area eludes me so far. I imagine this game would look spectacular if I had the graphics *Oomph!* to run it with. It looks pretty good even with my lowly card, using "low" geometry and 1.1 shaders...
I was impressed with the engine and the graphics of the demo. I didn't care too much for the repetitive single player gameplay. It feels like your just mowing through opponents with high powered weapons. I get the same feeling while mowing the lawn, which I hate, so I avoid things that remind me of it . I'm going to try the multiplayer tonight.