I've tried the Oculus Rift (and this very demo) last weekend with cairmen and werejud. It was very impressive, and when they have an HD one available I'll be interested.
The 3D is great - there's something about moving your head, even fractionally, to see different views that makes it work so much better than fixed-perspective 3D. I played the first few minutes of Half-Life 2 and spent time hypnotised by the face of the other person on the train. It is, to the casual onlooker, rather like watching someone on acid - Hugh told me about people staring at the rubbish bins in the train station "Ooooh, it goes all the way down, and the edges are amazing!"
I did get motion sick after about ten minutes, but I'm led to believe that this goes away over the first couple of weeks.
I also tried the Razer Hydra. Which, like many addons, claims to be the future of controllers. I played some Team Fortress 2 with it. It's impressive, feels nicely organic, and (like every other device that makes this claim) less accurate/fast than a keyboard/mouse. You can sweep nicely from side to side to aim/move, and I suspect a beginner would get to grips with it very quickly. But when I want to pick off an enemy combatant falling towards me firing their machine gun, I'll take WASD and a mouse every time.
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