Thanks for that summary, willz (and congrats on your first post). That really helped me see the "big deal" about Loopt. I read about it in pg's essays and visited the website, but I didn't see any extreme usefulness in an application that "shows you where your friends are." However, if it is expanded to the point of making recommendations, then I can indeed see the brilliance. It's like expanding Web 2.0 into the real world, isn't it?

That's very cool. I see, now. Although I can indeed as well think of many privacy concerns with Loopt (which Sam has probably solved), I wonder if you could use it as an aid to finding stolen or lost phones? Many possibilities come to mind.

This just adds to pg's thesis: startups are almost never what they start as, but what their users need them to become.