As soon as I saw this news story pop up on my Twitter feed, I had to click on it -->planets story<--.
Basically, astronomers are predicting that there is a strong likelihood of billions of Earth-like planets in our galaxy alone. I find this particularly cool because in my upcoming book, Blade of the Divided: The Divided Book 2, my angel characters travel to different Earth-like worlds.
I got really creative with my worlds, making some more medieval and primitive and others more advanced and futuristic. But if what the news story implies is true, there really could be other worlds like ours in different states of growth. And I think that's pretty darn cool.