The one thing these sorts of applications fail to address is quality-control: they're not in any way robust against those who would set out to deliberately pollute the simplistic databases used. We've had keyword-spamming and link-spamming against the popular search-engines; how long before we get similar georef-spamming against positional databases and a whole slew of bogus 1600 Pennsylvania Avenue webcams or sites claiming to display arrivals at London postcode SW1A 2AJ ?