My Little Pony: Friendship is Magic is receiving a Japanese dub! Here is some more information from Anime News Network:
At the "Bushiroad New Project Presentation" event in Tokyo on Wednesday, Bushiroad revealed that the cast of Tantei Opera Milky Holmes will dub Hasbro Studios' My Little Pony: Friendship is Magic animated television series into Japanese. The cast is as follows:
Suzuko Mimori (Milky Holmes' Sherlock Shellingford) as Pinkie Pie Sora Tokui (Milky Holmes' Nero Yuzurisaki) as Applejack Mikoi Sasaki (Milky Holmes' Hercule Barton) as Rarity Izumi Kitta (Milky Holmes' Cordelia Glauca) as Rainbow Dash
Bushiroad will announce the cast members for Twilight Sparkle and Fluttershy at an event in March. The show, renamed My Little Pony ~Tomodachi wa Mahō~, will premiere in April on TV Tokyo stations. The stations will air 52 30-minute episodes. The show will air in both Japanese and English.
You can see more images from the event here.