New Evolutions: There are now more opportunities to evolve your Pokémon in Pokémon GO than ever before. Some Pokémon originally discovered in the Kanto region will soon be able to evolve—into Pokémon that inhabit the Johto region! Be on the lookout for new Evolution items at PokéStops, which you’ll need to evolve some Pokémon.
New Encounter Gameplay: When you encounter Pokémon in the wild, don’t be surprised if they react in new ways as you’re trying to catch them. You’ll also notice the addition of new item carousels that allow you to select Berries and Poké Balls directly from the encounter screen. Hone your skills and catch those elusive Pokémon!
New Berries: Pokémon enjoy eating Berries, and you’ll have the opportunity to get two new Berries by spinning the Photo Disc at PokéStops—Nanab Berries and Pinap Berries! Giving a Pokémon a Nanab Berry will slow its movements, making it easier to catch. The Pinap Berry doubles the amount of Candy you’ll receive if your next catch attempt succeeds.
New Avatars and an Expanded Wardrobe: Now you’ll be able to give your avatar a complete upgrade! Customize your look with a whole new selection of hats, shirts, pants, and other items.
This game still seems to be a decent hit with people since it's currently the third most trending video on YouTube today.