Blizzard attempted to change the leveling process on many fronts -- easier XP, quests for dungeons at the beginning of said dungeon, and better quest flow. One of the more lively changes was quest loot being given more useful stats -- and more importantly, being made part of an overall more "matching" set. This meant that people who predominantly quest will find themselves looking put together, rather than wearing whatever scraps of material they roll over while trying to collect 20 bear bottoms. The sets may not always work with random "- of the X" drops, but overall, they look nicer and have a easily identifiable style and color scheme.
I'm quite impressed with this change. The strange mish-mash of leveling gear from questing was not only hideous to look at, it never matched and often had really terrible models with garish textures. The new questing gear looks regal and not prone to as much strange skin-baring, either. It looks like you're moving up the ranks of badassery as you are leveling up. This is a good feature! For those who are more inclined to roleplay, it gives you access to some easy outfits that you can wear around Stormwind or Ogrimmar and look trendy.
While I know this trend is going to stop dead in its tracks at Outland (which I will overcome by putting my heirloom gear back on), it is fun to see it present in the Azeroth leveling experience and further on in Cataclysm content. Are you happy about this change, or do you feel that the garish clown vomit outfits of years past were essential to people's game before the level cap?