When you zoomed out on the world, the map would be a mundane white. Now, it's got some color. And quite a bit of it.
Here's one of the examples Google uses on their Maps blog.
|Northern South America before|
|Northern South America after|
To see these changes, you need to go to map view (not satellite) and turn on the terrain option in the features bar on the right. Otherwise, the map stays white at some lower zoom levels and only gets color when you go far out. And the mountains and land formations are not visible without it enabled at any zoom level.
[Google Lat-Long Blog]