This movie is the second movie in the Pokémon Best Wishes Movie Series. It is scheduled for Japanese release in July 2012 and will likely, based on previous movies and events, offer a download of the event Pokémon Keldeo to your Black & White games.
This year, there has only been one movie announced so far and focuses on the Ice Dragon Kyurem as well as the Swordsman Pokémon; Cobalion, Terrakion and Virizion. Not much is known about the plot yet but Kyurem and the Swordsmen; Cobalion, Terrakion and Virizion battled in the mine in the mountain in the past, which created an Ice Dragon Gate in the process of battle so they could battle on the other side. However, now it's in the present, Kyurem appears again and the Swordsmen are back, ready to do battle with it.

Plot Details:
Ash and Co. head toward Rooshan/Roushan. While on a train passing through the mountains, Ash spots an injured Pokemon he's never seen before, collapsed. This is the phantom Pokemon, Keldeo who is said to be the successor to Cobalion and Co., the masters of the Sacred Sword who protect the world. At that moment, Kyurem appears and begins attacking, changing into Black Kyurem & White Kyurem in doing so. This blocks Ash & co's path to Keldeo. Ash and co. just manage to escape from Kyurem's pursuit, by the skin of their teeth. The battle rages between Kyurem, chasing Keldeo, and the train and hot-air balloon in the sky. Can Keldeo, Ash and co. overcome this danger?

It was later revealed that this movie would feature the legendary Pokémon Keldeo and the alternate forms for Kyurem; Black Kyurem & White Kyurem. The movie is also tied to a special short; Meloetta's Sparkling Recital

Posters

Fourtth Trailer Screencaps

Third Trailer Screencaps

Second Trailer Screencaps

First Trailer Screencaps