The game’s official website now has a link to sign up to be a field tester. Those who test will have to keep all of the content they see a secret. Ninantic is looking for people who live in the U.S., Australia, and New Zealand who own either an Android or an iOS device. Any progress you make while testing the game will not transfer to the final version. And your data could be wiped multiple times during the course of the field test.
The developers do warn that the game might not work correctly all the time. “The app is still in active development, so it has a limited set of features at the moment and there may be things that don’t work properly. We hope that you - as field testers - understand this and will work with us to make the Pokémon GO game experience truly phenomenal.”
Check out the trailer for the game: