There was a long discussion on HN on friday, you can find it here : <a href="http://news.ycombinator.com/item?id=4788902" rel="nofollow">http://news.ycombinator.com/item?id=4788902</a>
I wrote an article about the purpose of the game. Why it was built. you can check it out here if you like: <a href="http://news.ycombinator.com/item?id=4805229" rel="nofollow">http://news.ycombinator.com/item?id=4805229</a>
Somewhere in the brightly lit but somehow still dark recesses of Google, I am sure someone is writing a program right now that algorithmically generates games in order to distribute real world tasks onto humans. Just give it a spec in some map-reduce type query language, and up pops a new game on the Android store.
I was starting to lose faith in augmented/alternate reality apps picking up. But Google has nailed it here, and at a time when ARM chips are starting to be able to easily handle this sort of stuff, too, like with OpenCL and higher GPU performance. It also seems to be at least one of the "killer apps" of Google Glass.