Mega Evolutions at Pokemon ORAS: A Deeper Look at Mega Evolutions

Apart from being the anticipated remake of the Hoenn region, "Pokemon Omega Ruby and Alpha Sapphire" is looking to have quite the focus on Mega Evolutions.
In a blog post over at the official "Pokemon Omega Ruby and Alpha Sapphire" Web site, the developer details how Pokemons can actually achieve their Mega Evolution state, as not all Pokemons have this capability. At the same time, there are certain conditions that need to be met, which are just part of the mystery about how this phenomenon manifests.
"Pokemon Omega Ruby and Pokemon Alpha Sapphire tell a grand tale that draws ever closer to the heart of the secrets behind Mega Evolution, said to be the greatest mystery of the Pokemon world!" via the official Web site.

The two main conditions that need to be met as listed in the Web site are as follows:
1. The Trainer's Key Stone, worn on his or her person, must resonate with a Mega Stone held by the Pokemon.
2. There must be a strong bond between the Trainer and the Pokemon.

Note that there are Mega Stones for every Pokemon that has the capability to evolve to a Mega Evolution, with each stone having specific names. To date, 28 Mega Stones have been discovered. But given how The Pokemon Company and Game Freak have deemed it necessary to revisit the Hoenn region in "Pokemon Omega Ruby and Alpha Sapphire," there will surely be more hidden there.