Why is everyone hating on Vemane? Thundurus-T is a decent check to Tornadus-T in the respect that it can switch into a single Hurricane and force Tornadus-T out. Imo its too much like Jolteon though, in which case it only takes one Hurricane and can't switch in again (assuming rocks).
However, Tornadus-T has been proven to have many offensive checks. I've already explained why I feel Torn-T is broken so I'm not repeating myself; but, I think Vemane's point (or any Torn-T for OU point) is that offensive checks are easy to put on teams (and can even be considered "unintentional") and therefore makes Torn-T less intimidating.
This is somewhat true, but I feel that it doesn't take much to wear down any of Tornadus-T's checks, and the fact that Protect Tornadus-T can put pressure on Revenge Killing (which is what the majority of Torn-T's offensive checks are supposed to do) is why I still feel that this argument is moot.
Tornadus-T has too many ways around its checks. Between Taunt, (for its defensive checks), Protect, (for its offensive checks) and Sleep Talk , (for not being able to shut it down with sleep), just make Tornadus-T all the more threatening. It doesn't have a very consistent counter base, with Zapdos as the only Pokemon that can take everything Tornadus-T can throw at it (and even then SR damage is pwn'ing Zappy for like 25%). Hell, Tornadus-T even gets U-turn to stack more pressure on its already hard-pressed checks.
Also, like Melee Mewtwo said: Tailwind is legit.
tl;tr: Between Taunt, Protect, Tailwind, and Sleep Talk, Tornadus-T can easily narrow down its "checks". Meanwhile, the Specs set has more trouble vs. these offensive RK'ers but its bonus is hitting stall just so much harder with the aid of SR.