when you have a 70, you start to know how to level faster. it took me around three weeks of semi casual play to get my paladin to level 40. past 40 however, is where i slow down...A LOT, 40-60 = worst level grind in the game. so i have a 40 paladin, and a 40 rogue, that probably won't be leveling for a long time. i can almost guarantee i will have a 40 mage/hunter/warlock/druid/ or priest by the time i decide to touch my paladin or rogue again :_;
hell, ill probably get my warrior from 66-70 before i touch the 40-60 grind again. meaning, i would rather grind 66-70, with my prot warrior, solo, on this ganktastic server called illidan, than do 40-60.