Over on Google Earth Hacks we’ve just released GEboards, a completely in-Earth message board.
Following the release of Google Earth version 4.2, we realized that we could use the Flash player to accept text input in Google Earth. Many lines of code later, we have GEboards.
Once you load the KML, you can create threads about any location on earth – the restaurant down the road, the strange plane in the sky, etc. All of this happens without the need to use anything but Google Earth – not even the integrated web browser.