No, this is not vaporware! I'm actually able to walk and run in Far Cry 2 now using my treadmill. Actually, most of the time now have been with hacking with the Wii Remote! I'm currently tweaking around with a GlovePIE script, so I can use the Wiimote to be able to turn and change direction. Remember, walking on the treadmill only takes me back and forth. I want a cool way changing direction as well! And with the Wiimote I also get bonuses as the IR, the accelerometers build in and a few extra buttons. I also happen to have a gun holder, so I can transform the Wiimote into a "gun" which suits the game I'm testing this with perfectly. The Wiimote can also rumble, which it now does when shooting... The Nunchuck adds even more extra goodness!
One extra little thing that adds to the experience is that the game takes place in Africa, and since it's hot here now because of summer, it feels even more that I'm actually there. You sweat and get tired fast, hehe. Also, swinging the Nunchuck throws a grenade in the game...