Yeah, and not only is the XP nerfed but because it takes longer to kill mobs, you have two things dragging leveling down. I don't personally have a problem with 1-60. In fact, up til 65 it really isn't bad at all. Once you get to 65+ it starts slowing down significantly. I couldn't stand it and cheesed my way through that bracket by soloing BC heroics. I was getting a level per dungeon up to a certain point. I started a shadow priest, as well. At 55, it's taking me about 4-5 rotations to kill certain mobs one vs one. I am about to fall asleep playing that character. Blizzard has a habit of listening to feedback and then going way too far in one direction. They overcompensate. They just don't understand moderation. They want to do things correctly but they always over or under tune things. There are certain quests that are just plain broken. I'm also leveling a 25 warrior and just got done with the darkshire quest where you have to kill the abomination that attacks the town. In full heirloom armor, using every ability I have (including the 60% crit proc spell) I almost died killing it. I almost could not do it. Some mobs and some quests were not checked during the sweeping leveling changes.
A few things can be done that will fix the problems without pissing too many people off.
1) Mobs' healths need to be reduced a small amount based on time spent killed. It shouldn't take 4-5 rotations to kill a single mob outside of a dungeon.
2) Add world quests to every single zone. This will help boost XP earned for those willing to do them and add something to do that breaks up the monotony of questing.
3) Buff (to a small degree) the amount of XP mob kills give especially after 60.
The little baby that started this discussion here wants numbers even though he ignores them, so here's some info:
I was on my 75 warrior in outland (different warrior). I grabbed and completed about 10-12 quests each giving 4k-10k experience. I started doing that at about 50% xp to next level. When I turned them all in, I was at 70% to next level. I spent about a half an hour - an hour doing these quests. In that time, with that much effort, I gained 20% experience. That's boring.