Very recently, Google Earth received a major imagery update which dramatically improved the way land tiles were displayed. Countries and continents can now be seen as one continuous mass.
But Google isn't done yet, it's now addressing the other two thirds of the planet with a huge update to underwater terrain data. What this means is that the sea floor can now be explored in much greater detail than it has ever been possible in Google Earth.
"This new detail comes from spacecraft measurements of bumps and dips in the ocean surface as well as shipboard soundings from surveys carried out by over 40 countries," Google explained
"With this update to ocean terrain data in Google Earth, 15 percent of the seafloor is now available at 1 km resolution," it said.
All you have to do to enjoy the new terrain is to open up Google Earth and wait for the updated data to arrive.