There are two types of leveling in MMO's, one is fun, and one sucks. (Opinion.)

The first type of leveling is when the game released, everyone started @ level 1 and on mostly equal footing. Many of us pushed fast and hard towards the level cap, and we found other players with a similar skill level in our leveling range. Dungeons were challenging and new and fun to explore, quests weren't boring or burned out, and all said and done, this was fun. I leveled my rogue 1-60 this way, my warrior 60-70 this way, and my shaman 5 box team 70-80 this way.

The other type of leveling is post push. You already have a levelcap character, or you are a late starter. Either way this type of leveling generally sucks. You find yourself in empty zones devoid of other players, or you find yourself surrounded by players who have no interest in interacting with you, but simply want to push their alt # X to the levelcap. The quality of player you run into during this type of leveling are widely varied, some are smart and experienced players who are moving towards the cap smoothly, others are accidental levelers who got their current level by accidentally killing enough monsters to get there...