Balance Druid
Rotation
Opener: Mark of the Wild and Thorns out, Moonkin Form, Moonfire, Starfire or Wrath.
Priority: Moonfire up, then Starfire as the filler with Nature's Grace from crits; Wrath when moving or mana-light. Insect Swarm if the build has it. Innervate on the healer.
Cooldowns: Innervate (yours or the healer's), Nature's Swiftness with Healing Touch as the panic button, Hibernate and Entangling Roots for control.
Forever notes: Moonkin's crit aura makes it a buff bot in Forever's 10- and 20-player raids; the Nov 2 damage pass helps. Mana is the ceiling, so Spirit and mp5 gear is not wasted.
Stats
Spell Hit to 16%, Arcane and Nature spell power, Spell Crit (Vengeance and Nature's Grace), Intellect, then Spirit.
Moonkin Form's armor lets you take Stamina a little less seriously than a Mage.
Numbers for every spec and a gear comparer: stat weights.
Where it ranks
See the tier lists for PvE and PvP placement, and Classic vs Forever changes for what Blizzard altered in this class.
Wowhead and Icy Veins keep spec guides of their own: Icy Veins Balance Druid, Wowhead class guides. Our rotation notes are editorial, written for the Nov 2 tuning.