We have some recent news regarding Omega Ruby and Alpha Sapphire:

First off, we have three new confirmed Mega Evolutions: Gallade, Camerupt, and Sharpedo. The stat changes and ability of Mega Gallade have not yet been revealed, however the changes to Mega Sharpedo and Mega Camerupt have been released. Mega Camerupt will be given a lowered speed but a major jump in all it's other stats and its ability will be Sheer Force. Mega Sharpedo will have a small jump in all of its stats and will be given the ability Strong Jaw.

That's not the only piece of news that has been divulged today; some info on Primal Kyogre and Groudon have been revealed.

Primal Kyogre will be given the brand new ability Sea of Beginnings which will allow strong rain. Primal Groudon will be given the new ability Land of Endings which will allow strong sunlight.

Also, brand new moves will be given to the Primal Legendaries. Primal Groudon will be given a move called Cliff's Edge, however, Primal Kyogre's move has yet to be revealed.