This is just wild. The Burning Crusade expansion only just recently got released in China by The9, the company that runs World of Warcraft there, and a Horde Hunter named "SilverDragon" from the guild GreenBase has leveled from 60 to 70-- in just 23 hours (Warning: that link goes to a site that sells gold, so visit it at your own risk).
Think about that for a sec. When it was released here, the fastest leveler we saw took 28 hours, and he had the backing of a whole guild. Unfortunately, we don't have any other info about SilverDragon (gear? technique?), or any other confirmation that it actually happened, save for the "timestamped" screenshots posted on the goldseller's blog above. But if it is true, that is a crazy little chunk of leveling. Think we'll see an even quicker record to level 80?
Update: As commenter Andy notes, the top screen seems to show a Warlock. Except that Trolls can't be Warlocks, buddy. But he's right to be suspicious-- this may not be true.
Update2: OK, I think we've solved it (and can I just say I love how you can watch a train of thought slowly progress through any internet comment thread?). The shots are actually from different players, because they're targeting the same Hunter. And the reason the Troll looks different in the first shot is because that's the default Troll look-- whoever is targeting him is out of range, and in the second picture, they are not (which is probably why they have the Trueshot aura). Considering that there are also shots of him at 70 in the /who window, I'm going to call this confirmed. Congrats to SilverDragon for hitting 70 so quickly-- now he should probably go back and actually play the game.