The wow pvp system awards time and not skill, so if you don't have 12 hours a day for PVP'ing, going for exalted with one of the factions in the battlegrounds, will most likely get you better results gear-wise. The advantage of going for exalted with the BG factions is that your reputation gains aren't reliant on others, as it is with the PVP system, so you can gain rep when you want and it doesn't decay.

There are 3 battlegrounds; Alterac Valley (AV), Arathi Basin (AB) and Warsong Gulch (WG).

Arathi Basin
AB is (up to) 15 vs. 15 and is all about capping nodes and gathering resources from said nodes. There are 5 nodes on the map and the first side to 2000 points wins. The game is bracketed in the usual brackets from lvl 20 and up: (20-29, 30-39, 40-49, 50-59, 60). horde gain reputation with "The Forsaken Defilers" and alliance with "The League of Arathor".

Reputation is rewarded as follows (from wowwiki.com):

Quote: Quests, Reputation, and Other Rewards
Near each entrance is an NPC who gives quests related to Arathi Basin. One quest can be completed simply by participating in a certain number of Arathi Basin battles, and another requires you to win the battle.
Doing battle in Arathi Basin improves your reputation with The Defilers (horde) or The League of Arathor (alliance).
When your reputation reaches Friendly, you can purchase special items from a vendor NPC near the battleground entrance. Regardless of your reputation, you can always browse the special items, have your armor repaired, and sell items to the faction vendor.
Reputation rewards
Collecting multiples of 200 resources (at 200, 400, 600, …) = 10 rep (total 100 rep if you win)
Control Four Bases Quest = 800 rep
Win an AB Quest = 50 rep
On the Battlegrounds Holiday weekend for Arathi Basin, the Reputation rewards are:

Collecting multiples of 150 resources (at 150, 300, 450, …) = 10 rep (total 130 rep if you win)

Rewards

The rewards from being exalted with Defilers/League of Arathor are shoulders mostly, with a cape, a dagger and a staff thrown in the mix:

Shoulder armour
Highlander's Chain Pauldrons (hunter): Mail, 312 armour. +20 AGI, +18 STAM, +17 INT
Highlander's Epaulets (Priest, mage, warlock): Cloth, 185 armour. +18 STAM, +17 INT. Equip: Increases damage and healing done by magical spells and effects by up to 12. Restores 4 mana per 5 sec.
Highlander's Leather Spaulders (rogue, Druid): Leather, 258 armour. +12 AGI, +17 STAM, +12 INT. Equip: +30 Attack Power.
Highlander's Leather Spaulders (rogue, druid): Leather, 258 armour. +18 AGI, +17 STAM. Equip: +30 Attack Power.
Highlander's Lamellar Spaulders (Paladin): Plate, 553 armour. +18 STR, +17 AGI, +15 STAM, +10 INT.
Highlander's Plate Spaulders (Warrior, Paladin): +18 STR, +17 AGI, +20 STAM.

Back
Cloak of the honour guard: 50 armour. +5 AGI, +11 STAM. Equip: +34 attack power.

Weapons
Ironbark Staff: Staff, 136-243 damage, 3.4s, 55.8DPS. +19 STAM, +10 INT. Equip: Improves your chance to get a critical strike with spells by 2%. Increases damage and healing done by magical spells and effects by up to 41.
Sageclaw: Dagger, 46-96 damage, 1.7s, 41.7DPS. +8 STAM. Increases damage and healing done by magical spells and effects by up to 30. Improves your chance to get a critical strike with spells by 1%.

Other rewards at lower lvls of rep can be seen at http://www.worldofwarcraft.com/info/basics/factions/arathi/index.html

And there you have it. AB games are fast, so you will need to run a lot of them, and you need to win to rep up at a decent rate. Now it's up to you if you want to dedicate the time to repping