Common methods of power leveling include doing only those quests which are most efficient in terms of experience over time, and analyzing the quests in a given zone so as to do them in the most efficient order possible. Remember, the idea of power leveling is speed and efficiency--you may wish to obtain an addon that will show you how much experience per hour you are gaining to test your techniques. Additionally, ensure your character's talent build is crafted for maximum endurance. You want as little downtime (walking, drinking, eating, crafting, typing, etc.) as possible.
At Level 100, we recommend that you take the talent Unholy Frenzy. If you choose to take this talent over the other 2 options, then we recommend switching your Level 57 talent to Bursting Sores due to the great AoE synergy between these 2 talents. If you choose to use the talent Army of the Damned, which is an easier talent to play with, then we recommend staying with the Level 57 talent Ebon Fever.
Something to keep in mind as well is that this will make enchanting materials more valuable, since it is likely most players will now simply scrap their boe greens instead of getting them disenchanted. Also redundant dungeon/raid gear can be scrapped rather than traded to the (guild) enchanter in the run. Less stuff gets disenchanted, meaning there will be less ecnhanting materials, meaning their value will rise. All the more reason to DE rather than scrap as an ecnhanter.