In a statement released on their Official Twitter Page, Pokémon Go, made an announcement just a mere hour ago:
The official post goes on to thank the many players that have kept their dream possible over the course of two years, and to kick it off starting tomorrow, July 6th, there will be more spawns of Pikachu and Pichu in the wild. This electrified event will run from the start date until July 31st and will feature these special 'Mons' wearing a special "Summer Style.' It is unknown whether Pichu will actually spawn in the wild (they have only appeared in eggs since their release).
It also goes on to say that there will be a new 'Special Research' coming soon, which will feature the release of the 2nd Mythical Pokémon in the game, Celebi! The first 'Special Research' featured a slew of tasks for trainers to do from catching specific pokemon, to battling in enough gyms, and once completed, they were able to capture Mew--the first Mythical Pokémon from the original games and star of Pokémon: The First Movie (1999). Many speculate that these new tasks will be released in conjunction with their Pokémon Go Fest which is being held in Chicago (Lincoln Park) on July 14th and 15th.
Pokémon Go is available now on all mobile devices (iOS and Android) and is a free-to-play augmented reality monster capturing game made by Niantic in collaboration with Nintendo and The Pokémon Company.