Pokémon X and Y

Pokémon X (ポケットモンスターＸ) and Pokémon Y (ポケットモンスターＹ) are the upcoming video games of the Generation VI series. Pokémon X and Pokémon Y are the first two Pokémon video games that comes in the main game series for the Nintendo 3DS. The video games were announced by current Nintendo president Satoru Iwata on January 8, 2013 on and  during a Pokémon Direct video on the Nintendo 3DS. These will be the first video games of the Pokémon series that will be released worldwide with exception of different countries. Pokémon X and Pokémon Y will be released on October 2013, but the official release date of the video games is still unknown.

3D Enhancement
Pokémon X and Pokémon Y are the first two Pokémon games that are completely in a 3-dimensional style of gameplay on a handheld system. Each and everything has been changed since the release of previous Pokémon games. The sprites have been changed into 3D designed models from the characters to the Pokémon. The appearance of a Pokémon has also been changed as seen in the trailer when the male protagonist was running through the grass and encountered a Pikachu.

Battle System Enhancement
The battle system in video games also went under a 3-dimensional style. As seen in the trailer of the video game there were different Pokémon battles introduced. The attack of a Pokémon will be shown in a 3D style against another Pokémon. It will even show how the Pokémon will move when it's being attacked or vice versa by the opponent.

Starter Pokémon
The trailer also shows off three new Pokémon which appear to be the Fire, Grass and Water starters.
 * Chespin, a Grass-type Pokémon: a brown, Erinaceidae-looking Pokémon with a spiked green hat, small arms and a small tail.
 * Fennekin, a Fire-type Pokémon: an orange, fox-looking Pokémon with flame-like fur emerging from its ears. Fennekin also shares its name and appearance with the Fennec Fox.
 * Froakie, a Water-type Pokémon: a blue, frog-looking Pokémon with a white puffball on its back.

Mascots
The two legendary Pokémon that are the mascots for Pokémon X and Pokémon Y have been officially named as: Xerneas and Yveltal. Xerneas is deer-like with rainbow antlers, who is shaped like the letter X when it's legs are apart, while Yveltal bird-like avian of some sort, who is shaped like the letter Y.

Other
A new Eeveelution named Sylveon is confirmed. Mewtwo's Awakened Form.

List of New Pokémon and Forms in Generation VI

 * Chespin
 * Fennekin
 * Froakie
 * Sylveon
 * Xerneas
 * Yveltal
 * Mewtwo: Awakened Form

Inspiration
It can be possible that Pokémon X and Pokémon Y are based on Europe. During the trailer of the video game, Pikachu was standing on the Eiffel Tower, and an Eiffel Tower-like structure is seen behind the male protagonist when he's rollerskating in a city, also, the female protagonist has been seen running from a bridge which is probably modelled after the Palace of Versailles in France. Furthermore, when the screen is zoomed out at the start, it can be seen that Pikachu was also on Europe.

Interestingly, the two monuments showned in the trailer are in Île-de-France, a region inside France. This may hint that the in-games region might be based off that place.

Trivia

 * These are the first main Pokémon titles that uses single letters instead using colors or material items for the sub-title.
 * These are the first two games to have their mascot's English name released before their Japanese names.
 * In the Japanese logos, you can see a bit of DNA in the section: モンス. This could be a reference to how X and Y are chromosomes.
 * These games titles, X & Y, may also be reference to the 3D axis of X, Y and Z, since they're the first main games to be for the 3DS and to be completely 3D.
 * This Generation is bound to bring significant changes to the series:
 * A bond mechanic revealed by Junichi Masuda in his blog on 1/21/2013. This may be the way to get Sylveon.
 * 3D models for the characters and Pokémon.
 * 3D overworld.
 * These games are the first to introduce a new Pokémon form of an old Pokémon, Mewtwo.