★Update★

http://www.pokemon.co.jp/ex/xy/battle/04.html

Translates to...

So far, the number of times that can be evolved had a limit determined by the Pokemon. However, it exceeds its limit, the Megashinka,'s the further evolution.
To release temporarily the power I hid, Pokemon that you Megashinka exert force that can not be normal evolution.
Unlike the normal evolution, Megashinka occurs only during the battle. Pokemon with the Megashinka returns to the original battle is finished, but never want to return to the battle of. In addition, Pokemon that can be Megashinka in battle at a time, only one animal.
Some of the Pokemon that the Megashinka, some that ability not only go up, property types and change. To the one-shot reversal in the battle, it's also become an opportunity!
The Dase looking tools necessary for Megashinka, the "Mega Stone!"

The Megashinka, Pokemon not all can. I can be when certain conditions are met, only the Pokemon part, a Megashinka!
One of the conditions, to use a tool called "mega stones."

The "Mega Stone", a special stone that the number of Pokemon that can be the only Megashinka exist, with a name, respectively. For example, if the Lucario, Mega Stone of order to the Megashinka Lucario called "Lucario Night" exists.
To use the "mega stone" and attempts have as tools Pokemon. The first time, he is ready to Megashinka by Pokemon that can be the Megashinka is facing the battle with a "mega stone"!
Some of the "Mega Stone" seems to be what is secretly hidden somewhere in Karos region. In addition, any Pokemon or to Megashinka, where the mega Stone what is hidden, that it Sagashiateru them, is one of the ways to enjoy "Pokemon X · Y!"



Seems like Mega Evolution will not be easy to come by, It states that blaziken item will not be obtainable throughout normal gameplay O.o

Looks like you'll need to do all events, this Gen will be crazy!!!

↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓

⇒Not all Pokemon have Mega Evolutions.
In order to Mega Evolve the eligible Pokemon needs to be holding the Mega Stone.
As predicted the Mega Pokemon appear in battles only.
⇒Mega Evolutions have increased stats, with CoroCoro citing two examples: Mega Lucario has higher Attack and Mega Absol has higher Attack and Speed. Mega Mewtwo obviously has higher Speed as we saw in the Genesect film.
⇒The Blazikenite item cannot be found through normal gameplay.
⇒The Super Training area allows you to increase your Pokemon's "Kiso Points." These are probably what we fans have termed EVs all these years going by what our source said about the facility increasing EVs.
⇒A new area called the Master Tower is related to Mega Evolutions.
⇒The next CoroCoro will feature the new type chart reflecting the Fairy-type, new Pokemon, and new Mega Evolutions.

Woot! We'll finally learn all there is about this Fairy type! Also, EVs, or rather, "Kiso points," will finally be visible in game! I hope the same goes for IVs, or whatever they decide to call it!

Have they said if they are gonna release more Mega Evolutions or if this is all of them?

Never go full retard Gamefreak.

fairy type chart next month! im starting to suspect no show for starter evo! thats actually awesome. Nobody will kno starters intill you play, in the game for yourselves!

So how do they decide which ones megaevolve too? and is that the official name?

They get to choose watever they want, like which pokemon evolve or not. Its not a specific group or order. Im just hoping all starters get a mega Evolution

im actually talking about game freak deciding, because people are saying not all pokemon have this ability to do this, so is it a certain type that can mageevolve, do ALL pokemon in their final stage have the ability to megaevolve?  im probably over complicating this. lol