This game was first leaked a couple of years ago, but here's the official announcement:
https://www.youtube.com/watch?v=Y9j9RWkPstc
Now, I don't speak Japanese, but here's what I got out of it:
Release date: either 2 March or 3 February
3DS game
Takes place in
LONDON
O
N
D
O
N
You play as a talking Pikachu, who is unique because they also show a Pikachu that only says "pika".
>This game requires 800MB of space (6,400 blocks) to download and is listed on the official site as "Cinematic Adventure Game". It takes place in Rhyme City and you the human character called Tim Goodman who has come to the city for a currently unknown reason. When he meets with Pikachu, the story begins. It is a 1 Player game and has no online or communication features.
I want this game.