If there are two things that guarantee players in World of Warcraft a steady flow of cash, exp, and gear, it's running quests, and running PvP arenas. Now, considering that PvP guides are abundant in these parts, we'll be taking another look at experience modifiers for quests.

As a starter, you guys may remember the quest guide over at the WoW official site already enumerates a color-coded system to help guide players through quests they should be taking at specifics levels. These colors can be found on the exclamation points quest NPCs have over their heads, and are designated as such:

• Grey - Trivial
• Green - Easy
• Yellow - Normal
• Orange - Hard
• Red - Very Hard
  

• Except for grey quests (which give less exp), all quests from green to red will give the same amount of exp. There was an old rumor that started some months back that exp gains were determined by the color you picked, with red (hard) actually lowering your exp - this rumor has since been debunked.
• Grey quests give exp depending on the level the quest is grey to you. For example: If you start a quest that's at least five levels below your character's current level, for every additional level you're higher than the quest, the less exp you get (at least according to the WoWWiki calculations).
• While quests give the same exp irregardless of their color, specifics colors are ideal for certain character levels. Mike's advice here is to do yellow quests the most, red and orange when you can (have a party handy), and greens (the easiest) when you absolutely have to.