I like the underlying customer cause here - Let's get people off their chairs, on to the streets and meeting each other. Let's create interestingness in the mundane. Let's create a world which rewards interaction. A lovely antidote to the trend for us to all walk around with heads down, checking the latest irrelevancy on our smartphones.
It's also about spotting the beautiful in your surroundings; rather than just interestingness in the mundane, Ingress draws attention to art that you may not ever have looked at before despite walking past it every day. I've discovered a number of statues and sculptures while beta testing it that I genuinely had never noticed before.
I love the underlying engineering cause -- let's get everyone to keep a GPS/data link open while they walk around popular city attractions and roadways so we can build an amazing pedestrian pathfinding system.
