Alright, so a full-blown, Google-sanctioned version of "Google Earth live" is still probably 10-20 years away. But at least one company (other than Google) is pushing to make live, HD video of Earth a reality much, much sooner than that.
The company is called UrtheCast (pronounced "Earthcast"), and according to Google Creative Sandbox, their plan is to mount two cameras on the International Space Station that will not only stream live content at resolutions as low as one meter per pixel, but also "create a video version of Google Earth with the video playback and search functionality of YouTube."
Granted, UrtheCast's two-cam setup has its limitations. Google Earth Blog runs through a few of them:
1) For any particular orbit, you may not be able to view the desired location (too far over the horizon, too much of an angle). You might a have to wait dozens of orbits to get over that spot.
2) Daylight - you have to be over the location at the right time of day.
3) Weather - too many variables to count a) clouds b) haze c) pollution.
4) time of year can be a factor - sun angle too low, and weather.
5) Conflicting opportunities. How do you decide which place to have your camera aimed at when there are 100 different places to aim and you're moving at 17,500 mph?
But let's be honest here, people. The fact that in just a couple of years you could be spying on other parts of the world, live, FROM SPACE... is pretty amazing — and definitely a sign of things to come. [UrtheCast via Google Creative Sandbox + Google Earth Blog]