I played around with it at the weekend.
My machine is an athlon 3200+ XP 512 Mb DDR 400 Memory with an ATI 9800 Pro graphics card, so it’s reasonably high end.
The gameplay is pretty much exactly the same as before except that the flashbangs are really awesome now (they deafen you, then make your ears buzz, along with appropriate ghosting of on-screen images, it’s a really cool effect). You have better interactions with objects on the level as well, but that’s not hugely important. Other than that it’s CS with better graphics.
The graphics are pretty damn good, de_dust isn’t the greatest choice for a tech demo as it’s quite texturally similar throughout the entire level (no water, lots of yellow/brown rock) But there are some very nice touches. Entering the central indoor area where the first battle is inevitably fought you notice that they have added a light source above the central chamber, with light entering through several cut outs in the roof, highlighting dust motes and generally looking nice. Most impressive to me though was the subtle relection from the rough tiled floor, rippling most convincingly as you run along.
The character models and physics engine appears competent. Shooting someone againt a wall ends up with them slumped against it and all the various ragdoll stuff you would expect from the modern era of FPS’s. One slight problem I have is that if you’re hit by a barrel rolling down a hill (for example as you come up on the CT side of the underpass) the barrel just stops, there appears to be no modelling done for the momentum being conserved in collisions between the player and moving object. I’m not sure whether this is an engine or level design flaw. I particularly liked the way weapons and bodies on the ground are thrown about by HE grenades, looks good.
In comparison to Doom 3 it feels like the engine is lighter to me, frame rates were much better for me and I couldn’t see any realy quality advantage for either engine. I may however be biased by the fact that I’ve always preferred half life over doom for level design though, too much darkness in doom.
Overall the demo looks good, plays well and holds subtle promise, but I doubt it’ll blow anyone away.