Yeah, just posting to say that imo, this is the first BW OU team I've seen that honestly can't get any better. If you are a skilled player, then you will win with this team. There are some move choices that could be changed, but I feel as if you could argue for every single move you have chosen and every ev you have distributed.
With that being said, a minor nitpick I would consider is using leftovers over black sludge on tentacruel. A smart player can take advantage of tricking black sludge back to one of your pokes that wouldn't enjoy it. Unless you have a reason for using black sludge > leftovers that I'm not catching. Also, you have a generally slow team, and I think putting thunder wave on at least one of dragonite, ferrothorn, or blissey would be beneficial for you, replacing thunder, gyro ball, or toxic, respectively.
Other than that, great team, I've already started to play it every other time I'm on the ladder lol.