How is Mega evolution going to affect Ditto?

Thanks to Imposter it has finally become a little useful, but will this little motherfucker just change into the normal form of a mega pokémon?
Or will it change into whatever is in front of it and therefore make it so that you can have a possible second mega on your team?

And do you think there'll ever be a Mega Ditto?

Personally I think we'll find that regular Ditto can only transform into the foe's regular form,
but once Mega Ditto is released, it can change into a mega

Heck, maybe Mega Ditto can transform into the foe's Mega form, regardless if the opponent has mega evolved yet. Could make for some interesting outcomes, especially if the opponent has more than one pokémon on his team that has a mega form