I'm not inclined to seek out the numbers and crunch data...but I swear legendary weapons sure seem to drop more often than you'd expect.
The Burning Crusade was released in China back in September, yet one ambitious guild has downed Illidan already and guess what? A legendary dropped.
IIRC, the first Ashbringer dropped early on when one of the top guild's during the Naxxramas era.
And it didn't seem long after Blizzard added the druid epic flight form quest that players were coming away with the raven mount, I think the next day?
Now I'm not complaining, and WoW does have a lot of players, but I wouldn't put it past Blizzard to conveniently have a much looser loot table at the beginning of things, just as advertisement.
2 hours ago