Those cards are insane! That Crisis Vine from that Mega Venusaur would destroy me. I would hate to see that paired up with a Virbank Gym card. Did you see the new EX versions of their previous evolutions? I heard rumors that Mega Pokemon can only evolve from EX. So, the pokemon company have also released EX versions of Venusaur and Blastoise. And the thing is, both of the newly released cards are basic pokemon, which would make their mega evolution alot more usable.
You can see the full image of the new EX cards here.