Leveling is pretty painless now if you are rolling in Heriloom Hat, Shoulder, Chest, Legs, Back and Weapon. Even better if you have the trinkets. Hardest part is getting to level 15 to queue for instances. I know there is a discussion abour grinding in Deepholm for speed. I would be willing to bet a tankadin/blood DK + healer + 3 lowbie bots could fly out there after 15 for summoning stone and level quickly. There is a link around here for the AOE grinding spots in Deepholm/Twilight Highlands.