Primal Reversion?

In Omega Ruby and Alpha Sapphire, Kyogre and Groudon gain new forms of their own. They are called Primal forms which work kinda like mega evolution's, except they come from a process called "Primal Reversion" where Kyogre and Groudon regain the forms they had during prehistoric times. I'm not sure what new powers Kyogre and Groudon get with their primal forms, but I hope they get new abilities, and at least one of them gets a new type. Cause I think new forms would be a waste without a certain kind of change that would help the Pokemon through problems they had before. What about you? What are your thoughts about all this?