I lost last round, but i think that i can comment right? Answering to Joeyboy's petition...
Rain is a weather that has completely changed the whole metagame, as new pokemons just like Keldeo, Tornadus-t, Thundurus-T, Ferrothorn, Tentacruel, etc have found their place on their favorite weather.
Anyways, people think that things that Tornadus or Thundurus are OP. However, i think that they are powerful but not OP. This is what i like about the OU metagame, the multiple ways to make a team using different playstyles in only one Tier and break your head trying to make a team that counter/checks threats as the mentioned before.
THOSE THREATS are what the metagame needed, something that can put more difficulty at the teambuilding, something to reach, to be the very best ever.
In my opinion without those pokes, those that make the metagame more dangerous, the competitive playing would be kinda boring.