The premise of The Thieves and the 1,000 Pokémon is to befriend and collect Pokémon through StreetPass. You can use Pokémon to take on the band of thieves and their Pokémon by clashing in stampede-style battles to retrieve stolen treasure.
If you don't have enough Pokémon, you'll end up losing against the thieves, so you'll actually need to have quite a lot of Pokémon to get far in the game. The villains are characters who'll be appearing in the upcoming film, Pokémon the Movie: Diancie and the Cocoon of Destruction.
The trailer also mentions that there's a special something in store for those who play the game and take it to the movie theaters when the new Pokémon movie premieres. There will also be something special for those with Pokémon X and Y.
Nintendo has no plans to include same sex relationships in the North American release of Tomodachi Life and says they're just trying to make a "playful alternate world." In a statement, they said:
Nintendo never intended to make any form of social commentary with the launch of Tomodachi Life. The relationship options in the game represent a playful alternate world rather than a real-life simulation. We hope that all of our fans will see that Tomodachi Life was intended to be a whimsical and quirky game, and that we were absolutely not trying to provide social commentary.
The internet has responded with a call for #Miiquality, asking Nintendo to include same sex relationships. If you're interested, check out Miiquality on Twitter.
Update: Nintendo has issued an apology, saying changing the game now is just not feasible, but future Tomodachi games will see more inclusivity:
We apologize for disappointing many people by failing to include same-sex relationships in Tomodachi Life. Unfortunately, it is not possible for us to change this game's design, and such a significant development change can't be accomplished with a post-ship patch. At Nintendo, dedication has always meant going beyond the games to promote a sense of community, and to share a spirit of fun and joy. We are committed to advancing our longtime company values of fun and entertainment for everyone. We pledge that if we create a next installment in the Tomodachi series, we will strive to design a game-play experience from the ground up that is more inclusive, and better represents all players.