Google is REALLY watching now. John Battelle blogs:

Not content to lease data from others who have satellites, Google today launched its own satellite into space. (Via BeetTv, thanks Andy.) Talk about web meets world....this is yet another indicator of the integration of virtual and physical. And it brings Google one step closer to what I think could be the company's Waterloo - a viral meme that Google is sensing too much, knows too much, and is too powerful. It may not be rational, but no one ever accused humans of being entirely rational.

A Delta 2 rocket carrying the GeoEye-1 satellite lifted off at 11:50 a.m. Saturday. Video on the GeoEye Web site showed the satellite separating from the rocket moments later on its way to an eventual polar orbit. The satellite makers say GeoEye-1 has the highest resolution of any commercial imaging system. It can collect images from orbit with enough detail to show home plate on a baseball diamond.

In a speech last month to a security conference in the UK, Stoica explained that by using shadows you can read the length and rhythm of someone's gait and do an identification, even from above. He has written software that isolates the shadow from video, and adjusts for time of day and camera angle to deal with elongated and foreshortened shadows. Stoica shot video from the top of a six story building to test out his software and was able to get usable gait data on his subjects.

Now going from six stories to satellites in low Earth orbit is probably a stretch. The best commercial low Earth orbit satellite (GeoEye- launching this Sunday to power better Google Maps) will have 41 cm resolution. The best known military spy sat can see at least down to 10 cm (though who knows what classified hardware can do). GeoEye is also only taking stills as it flies over, not the kinds of video footage that Stoica was using. To do that, you might need to go up to geostationary orbit which is much farther out and according to one expert, just wouldn't have the resolution. Unmanned aerial vehicles (UAVs) flying overhead, on the other hand, might work just fine for this.

Either way, you may want to practice skipping from place to place when it is sunny out.