I've got my Shaman to 49 and my Mage to 50 now and I sit waiting to drudge through the task of getting to 58. 58 is the magic number because that is when you can go to outlands and when leveling becomes laughable. There are so many options and some of them even in areas I like. I love Un'Goro Crater. Most likely one of my favorite places to level. Even more so if you happen to be a leatherworker or a miner. Either of those, this is a paradise. You will end up with so much of everything that you will not know what to do with it all.
It just seems that making it from 48-58 takes forever. Even if there are lots of places to quest and lots of good quests to work it, it seems like the experience gain is horrible. I could do a level an hour up to about 40. It slows down slightly after that, but once you reach those 50s it seems like 3 or 4 hours per level. Even doing the same things you did before.
Lots of people have been saying that the LFD is the way to go but I would have to disagree big time. It is good when used with questing but not as the only way to level. I got my Mage from 1-45 in 2 days, 45-50 took almost a day all by itself because I used the LFD. I decided to do that being the quests where so spread out. Figured it would be nice and quick and a way to jump from a bad quest hub area to a better one. I was wrong. How can I do 45 levels in 2 days and 5 in one day? Because dungeons give really crap experience and they take forever and a day to run through. I've spent an hour in a dungeon for 1/3 of a levels experience. I could have easily did 3 quests in much less time and got that much experience. Unless you have an uber group that burns through dungeons then leveling with them is not a quick way to level.
I can't wait until I get to outlands. Once there questing becomes so much easier. No longer do I not take a quest because it takes to long to get there and back. I either grab it and fly there and back or I grab it knowing when I am in the area I can do it and fly back whenever I am close. When walking it takes forever so I do not bother with quests like that. Even more so quests that go from one continent to another or even one area to another if they are not connected areas. Those quests are s complete and total waste of time if you ask me. When I leveled my first character they were great to see the world. Now I have seen the world so many times I just do not want to waste all my day traveling for one stupid quest.
I hope that is something they updated for Cataclysm. They say they updated quests and as such, movement is the one thing I think needed to be updated. Drop rate on some items needs to as well. Well, hopefully next week I will be in outlands with one or even both of those characters.