Should you dual spec?

Dual spec... is it really worth it?

cost: 1000 gold

This is alot of gold to drop for dual spec ability. So is it really worth it???
Answer: Depends on your class and if you are raiding.
Q: So who should dual spec?
A: Tanks and Healers mainly if you are raiding.
Q: Why tanks and healers?
A: Both can second spec to a DPS spec in case their primary specs are filled in the raid already. The exception class is the Paladin who can choose 2 out of the 3 rolls.
Q: What about mages, warlocks, and hunters?
A: Those are just pure DPS classes, who would dual spec for 1 purpose raiding spec vs. PVE/PVP spec. Warlocks and Hunters will dual spec with pet spec for PVE and max DPS spec for raiding. Hunter's will also dual spec because of exotic pets, namely the spirit beast's. Hunter's collect pets to showcase to other hunter's and players.
Q: Which class(s) are best for dual spec?
A: Shaman's, Druids, and Priest's who are spec'd in the caster DPS tree and Resto/healing tree. Reason for this is quite simple, you won't have to switch gear based on spec. Also during raiding you can switch in between fights and give your group an advantage to extra healing or DPS.

So it would still only cost 1000 gold for the dual spec?
Yeah, oh but don't forget to open your wallets and spend what you have left if any on the following items:
1) Glyphs for second spec
2) Skill training for second spec
3) Possible new gear for second spec
4) Possible new gems also for second set of gear

Some of these items can be pretty costly.

So remember these tips and think twice before spending the thousand gold to have a second spec.