They reduced the XP you gain while levelling, which is a good thing in my opinion. At this moment I have to make sure my character is not using heirlooms and is not in a resting/area when logging out, to make sure I do not outlevel the zone. And still I sometimes skip quest/hubs. Not even starting on the fact that doing dungeons really screw stings over.
A lot of people are complaining about this, ´We don´t want to level longer´ , but you have a choice, equip Heirlooms, and outlevel everything fast enough. Although I would wish that if you have no heirlooms, your damage would scale up in dungeons, so you at least have the idea you are doing something meaningfull..that, or reducing the power of the heilooms, not the XP-gain.
But new players will..STOP there.. they are new players, do not speak for them, and let them eperience the game at their own pace. And don´t give me that stuff that the game does not start before max. World of Warcraft does not start at level 100-110 anymore. There is so many to do outside end/game stuff.
But now they cannot play with their friends that are max/level? Wait..what? Why can't they do that? This is more a problem of not helping your low level friends, than not the option to do it. Be in the same guild already makes you play together more. Or start levelling a low-level character yourself to help your friend. Playing with friends goes two-ways people...
And then some so-called altoholics come by, and proclaiming that no one wants to slow level because you want to be max-level at all alts... well..boohoo... I am an altoholoic, and I actually like doing lower level dungeons..once in a while, although strong heirlooms take away the fun.again, do not talk for everybody /sigh. And having multiple alts was never meant to be easy.
At the moment I have 15? level 100's...and guess what? Even before the Beta, I was hardly playing them, because you only have so much time.. and it doing the same daily on 15 characters after each other... well, hello burnout?
You know, I actually don't mind outlevelling a zone that much, as long as there is a story to end. To make a choice is not a problem, and I would not mind skipping half the quests, Problem - is, that all zones have story-lines that are hard to break up, on big story per zone. Which makes me do the odd not-logging-out-in resting-zones-and-no-dungeons.
I think Blizzard did not go far enough, they should really scale down the heirlooms to their level, The raw power is so big, that, as mentioned before, doing dungeons as non-heirloomed characters really is not fun. Actually, as a heirloomed Char it mostly not fun..suff dies so fast, not even starting about all those rolin tanks. And for that matter, increasing their XP-gain would also help. People who really just want to level, would do so faster, and you would have the choice to go without more XP... but with the same power.
TL;DR Good Job Blizzard, now, scale down the power of Heirlooms and increase their XP-gain (So the levelling-time takes about the same time)