In this Boomkin (Balance) Druid guide I'll show you all the most common character setups for all aspects of gameplay in PvP. Keep in mind that different arena combos, arena sizes, battlegrounds, and rated battlegrounds can benefit from a variety of different setups for your Boomkin. This guide aims to give every player a general idea of what your talents, gems, stats, etc should be like but, don't be afraid to try mixing things up to fit your playstyle and PvP area of choice.

Balance Druid | Best Spec/Talents and Glyphs

Below is a general idea of the talents I suggest. Feel free to make changes for your playstyle and group makeup. For example Ursol's Vortex can be switched out for Disorienting Roar if you feel that it benefits you more.

[Glyph of the Moonbeast] Essential. Greatly improved utility and survivability.
[Glyph of Barkskin] Suggested. Good for survival.
[Glyph of Solar Beam] Suggested. Decent boost to crowd control.
[Glyph of Nature's Grasp] Optional. Helps with melee.

Any other Glyphs are totally up to you.

Minor Glyphs

[Glyph of Grace]Suggested. Great for fall damage reduction.
[Glyph of the Stag]Optional. Adds mobility for your team.

Any other Glyphs are totally up to you.

Balance Druid | Best Stat Priority

Simple: 6% Spell Hit (Hit/Spirit) > PvP Power > Intellect > PvP Resilience > Haste > Mastery > Critical Strike

6% Spell Hit (Hit/Spirit): 0% chance to miss versus other level 90 players in PvP.
PvP Power: Increases damage to other players and their pets/minions.
Intellect: Increases damage/healing done by all spells and very slightly improves critical strike chance.
PvP Resilience: Reduces damage taken from other players.
Haste: Decreases cast time and DoT tick speed.
Mastery: Increases damage bonus during eclipse.
Critical Strike: Increase the chance to critically strike for 200% damage.

Balance Druid | Best Gems, Enchants, and Reforging

Below are some suggested gems. Obviously for different scenarios you might want to switch things up. For example when I'm doing RBGs I tend to get focused immediately so, I may want more PvP Resilience to reduce damage taken instead of going with other stats on my gems.
Meta: [Burning Primal Diamond] [Forlorn Primal Diamond]
Prismatic: [Stormy River's Heart] [Mystic Sun's Radiance]
Blue: [Stormy River's Heart] [Vivid Wild Jade]
Red: [Mysterious Imperial Amethyst] [Willful Vermilion Onyx]
Yellow: [Shattered Wild Jade] [Effulgent Wild Jade] [Vivid Wild Jade]

Enchants

Shoulders: [Greater Crane Wing Inscription]
Cloak: [Enchant Cloak - Superior Intellect]
Chest: [Enchant Chest - Super Resilience]
Bracers: [Enchant Bracer - Super Intellect]
Gloves: [Enchant Gloves - Greater Haste] or [Enchant Gloves - Superior Mastery]
Belt: [Living Steel Belt Buckle]
Legs: [Greater Cerulean Spellthread]
Boots: [Enchant Boots - Greater Haste] or [Enchant Boots - Pandaren's Step]
Main Hand: [Enchant Weapon - Jade Spirit]
Off-Hand: [Enchant Off-Hand - Major Intellect]
Two-Hand: [Enchant Weapon - Jade Spirit]

Balance Druid | Profession Perks

For professions you can go with whatever you like (I have Alchemy and Jewelcrafting) but if you're trying to get the best professions for a Boomkin in PvP, then you'll want to go with Blacksmithing and Engineering.

Alchemy: [Flask of Enhancement]
Blacksmithing: [Socket Bracer] and [Socket Gloves]
Enchanting: [Enchant Ring - Greater Intellect] x 2
Engineering: [Synapse Springs] and [Nitro Boosts]
Inscription: [Secret Crane Wing Inscription]
Jewelcrafting: [Brilliant Serpent's Eye] x 2
Leatherworking: [Fur Lining - Intellect]
Tailoring: [Lightweave Embroidery]

Skinning: [Master of Anatomy]
Mining: [Toughness]
Herbalism: [Lifeblood]