Thats quite interesting. Skyhook location, though (my wife has an iPod Touch) is really inaccurate at times. Often off by a quarter to two miles.
There’s already software out there that can syncronize a GPS’ track log with photographs – provides that your clocks are reasonably synced up. Presumably, the iPhone would need to be recording a track log. Sounds like a dreaded battery drain. Still – cool idea.