What are the bonuses of each Dragon color?

Devran

I didn't actually know the dragon color made a difference. Does someone have a list they can post of each color and the benefits of each?

Halos

The differences between dragon colors are very tiny.

From HELP DRAGONS

It should be noted that there are no particular alignments or personality traits associated with the different kinds of Greater Dragon. That sort of simplicity is only found in the lesser dragons. Indeed, the only difference between the colours is that each has a different breath weapon.

Each breath weapon is a different damage type.

Red - Fire damage
Blue - Cold damage
Green - Poison damage
Silver - Electric damage
Gold - Psychic damage
Black - Acid damage

Since this is the only difference, this is all anyone talks about (aside from aesthetics). So usually the conversation goes into about how many damage resistances are against each type of damage. Magical resistance rings and caloric salve and frost elixir for example. There's a way to mitigate all these damage types except acid.

I assume you've read this thread

Some of the battlerage attacks are different too.

Also this thread http://forums.achaea.com/discussion/5003/what-is-the-best-colour-for-dragonform-bashing-in-any-given-scenario

Aerek said:

Red, Gold, and Silver, I've been led to believe are the best by my experience and public opinion.

• Red is good by itself because Dragonblaze is its "big" Battlerage damage attack, but its damage-over-time nature means a high critical rate can make it do more damage than the other dragons' upfront attacks on average. It also has the Inhibit affliction, which is -supposed- to stop NPCs that heal themselves from doing so, which I find theoretically strong, but its duration is short and I've heard it's always been bugged and non-functional anyway. Still, when I bash, it's usually in Red.
• Gold is good because its Aeon and Amnesia afflictions help handle big-name NPCs that actually do hurt you. Amnesia is the stronger, the NPC will lose about 3 attacks on you, (I don't know if it's just a set duration, or it actually counts the number of attacks they forget) but that's enough to catch your breath when you're throwing down with some of the big name and honors mobs. Aeon isn't as good, but it still hits their DPS, and you can use it while Amnesia is on cooldown. This just gives you the flexibility to use Overwhelm/Psiblast for damage, or Psidaze/Deaden for survivability.
  
• Silver I've heard/thought is good because theoretically you can micromanage it to give the NPC sensitivity right before one of your big attacks. It sounds good on paper, but I've admittedly never bothered with it because I don't really bash enough to put that kind of time and effort into it, and I haven't actually tested to see if a sensitivity/Dragonspark/Gut combo actually does more damage than just using Dragonspark/Overwhelm/Gut for the same amount of rage.

That's all for solo work. I've never bothered with deep group battlerage tactics, because after some initial number crunching it just always appeared that group DPS was higher if everyone just spammed their damage abilities instead of trying to utilize the affliction-exploiting bursts.

Morthif

Silver has 42% increased sexiness also. 

Farrah

The different breath weapons give different afflictions, as well.

Red - ablaze
Blue - shivering
Green - loki

Gold - disruption
Silver - epilepsy
Black - nothing, just damage

Blue is considered good at 1v1 in part because of how shivering from breathstorm stacks well with leg breaks.

Green, on the other hand, is unpredictable. Silver can just be FOCUSed off, and Black has no aff.

Fire affliction should stack well with the leg breaks too, but fire is the most heavily resisted damage type, so I don't know that it ends up worth it.

Gold's passive disruption is neat, though doesn't proc as often as the others.

Ultimately though, all the breath weapons suffice. You can pick based on flavor if you want to.