No, according to our buddy Ghostcrawler. He says that Blizzard's goal this time around was to avoid the Karazhan mistake from the last expansion, where players butted their heads up against tougher content in the early endgame. GC says that Blizzard certainly knows how to make tougher content, but they'd rather everyone got a turn this time around.
The only question I have left is why they didn't include it all in the same release -- Blizzard seems to be saying that harder content is on the way, but wouldn't it be more prudent to have both easy and hard content in at the same time? As a casual player, I'm thrilled to hear that the endgame is easier -- I'll get to see more of it. But we've got two versions of each endgame instance now -- do they both have to be easy enough to conquer in a few days?