Despite being mostly made up of plate-wearers, the Death Knight faction actually buy wow gold some pretty useful rewards for other classes. If you're a Leatherworker, the Nerubian Reinforced Quiver pattern is obtainable at honored.

You'll definitely want to get at least revered with these guys, as the Arcanum of Torment is the PvE Hunter helm enchantment of choice. In addition, revered reputation also grants you access to the Spaulders of the Black Arrow, a solid set of DPS shoulders. For weapons, the Runeblade of Demonstrable Power is nice for Marksmanship and Survival Hunters, with a solid balance of agility, attack power, haste rating, and critical strike rating that blow old high-end favorites like The Blade of Harbingers out of the water. Dual wielders may also find that the Reaper of Dark Souls is a good upgrade for them. All of these rewards are, of course, level 80.

As you can see, you can find an excuse to grind just about any reputation in Wrath you want. In the end, it's probably up to you to decide what's most important to you. Me, if I was pressed for time, I'd probably focus on the Argent Crusade, the Oracles, and the Kalu'ak. All three have rewards both useful and fun that I really want to get my hands on. But look over the rewards, take as much time as you need, and then choose. But choose quickly. After all, the next expansion may only be a couple of years away.