I HATE leveling. Not because it's not hard, but because it's boring. And it's not boring because it's not hard, it's boring because:
- The classes are not interesting before max level
- We've been doing the same kind of quests over and over for 10 years
- The leveling zones are empty
- The gameplay is painfully slow
- It's just a part that I don't have any interest in but that is 100% mandatory for the other 90% of the game
The only logical reason for Blizzard to increase the time needed to go to level 100 is for the new players they're expecting to come with the movie (which is probably not going to be a large number anyway), but
- New players are not experienced in the game, so it's going to take them a lot of time anyway
- They don't have access to heirlooms
Considering this, and the fact that the leveling experience is bad (and not because it's "too fast"), I really, really, really don't understand why is Blizzard punishing the current players for the sake of providing a slightly better experience to players that are most likely going to stop after the free month.
And actually, I'm not even concerned directly by the change since I already have all classes at least level 90.