Really though, if you guys want something radically new, try this on for size.
Have any of you heard of AR? (Augmented Reality)
It's being developed by (mostly) private inventors and programmers right now. Won't hit the market for many years yet, but still worth knowing about.
Picture this: you're walking down the street, wearing a stylish pair of specs that are beaming images into your eyes, images that overlay what you're seeing in reality. The images convey info to you from a small computer you're wearing on you somewhere, all wirelessly. (The specs are probably powered via the electromagnetic field your body generates.) The computer is connected to the Internet, and an advanced GPS, it can keep track of which way you're looking with your eyes (combo of the GPS and a little monitor in the specs). So, forget having to hold a Blackberry and follow its navi around, your path will literally be illuminated in front of you, plus you'll be able to look at a building or a monument and instantly pull up all available info on it. Also, your AR unit will recognize the faces of the people you meet and remind you of their names when you see them again.
So --- that's not a game, but imagine the possibility's for games. Scavenger hunts. Tag. Races from checkpoint to checkpoint (the checkpoints could just be floating balls of light or rings that you have to actually walk through). The possibilities are enormous. Capture the flag on a huge scale.