This augmented reality thing is crazy. I was skeptical when I first heard about it, but every demo I have seen has blown my mind. This is by far the coolest application of AR that I have seen.
Other than some obvious software bundled with the iPhone (like google maps, etc.), this is probably one of the best uses of the platform I've seen so far. It's useful to me personally, very innovative in a really cool way, and has potential to be huge. There is a shortage of innovative iPhone apps that are also useful, and you guys knocked it out of the ballpark. This sounds like perfect software for Apple to put into their commercial.
I don't know the GraffitiGeo guys, but I really doubt they "stole" the name. I think we're seeing convergent evolution at work here - it's a logical combination of words to describe "leaving digital marks on the real world".
With Foursquare, I often find myself wanting to be the mayor of my neighborhood, since I've had up to 5 mayorships in a 1 mile radius (a small distance in Los Angeles). GraffitiGeo seems to be addressing this.
