It's just going to be a short blog post here (for once I'm actually doing it right!) about the small range of buffs that classes can do that are unique to the target, or in effect you can't cast them on more than one person, or you can't stack buffs of the same style onto the same person. Confusing intro, hopefully it'll be explained down below.
It's going to be outdated soon enough in the 4.0 patch, but I'll first talk about Paladin Blessings, These come in 3-4 flavours, depending on your spec, and have certain priority over what to buff who. I HIGHLY recommend the addon PallyPower, just to make things easier for buff assignments in a raid. I'll put in a list below of what each role will want over other blessings:
Abbreviations
BoK - Blessing of Kings
BoM - Blessing of Might
BoW - Blessing of Wisdom
BoS - Blessing of Sanctuary (Protection only)
Pre-4.0
Tanks: BoS, BoK, BoM, BoW*
Physical± DPS: BoM, BoK, BoS, BoW*
Casters and Healers: BoK, BoW, BoS
Note: If you have BoM or BoW improved, cast it. If not, you might be better off using another buff and getting a Warrior to Battle Shout, or a Shaman to use Mana Spring Totem. And don't forget about Drums f the Forgotten Kings too!
* BoW only on the classes that use mana of course, like Paladins etc
± Physical DPS includes Hunters.
After patch 4.0, the priority system gets much simpler. BoS has
gone, and has turned into the talent Sanctuary which is a passive effect. BoW has merged its effects into BoM, so effectively Paladins now have 2 buffs to choose from, and with mana management being more challenging, the Blessing priorities appear to be the following at the moment:
gone, and has turned into the talent Sanctuary which is a passive effect. BoW has merged its effects into BoM, so effectively Paladins now have 2 buffs to choose from, and with mana management being more challenging, the Blessing priorities appear to be the following at the moment:
Post-4.0
Tanks: BoK, BoM
Everyone else: BoM, BoK
Now onto Paladin Auras! This is pretty simple for Paladins, generally in ICC you want Devotion Aura up as main priority, as most fights use physical damage that isn't spike damage. Next up is whatever you have the main improvement in, so Holy will generally go for Concentration, while Retribution will go for... Retribution. Different fights have different priorities though, and it's important to use your head as to what's best. On Sindragosa, it might be better to swap out Devo for Frost Resist, for example. And again, to help with organising auras, download PallyPower!
Next stop is for Warriors. They have two things to make a decision on; firstly is their Shout buffs. They have a choice of either Battle Shout, increasing raid's physical DPS, or Commanding Shout, increasing raid's health. Both of these are shared with other class buffs, so just use the best with whichever setup you have. Retribution Paladins will be able to overwrite your Battle Shout, and your Commanding Shout will overwrite a Warlock Imp's Blood Pact. But you may as well have either BoM and CS, or BP and BS, so adjust accordingly.
The second thing for Warriors to think about - well, of the Protection variety - is Vigilance. Who to put it on? There is a bit of controversy as to who to put this on, most Warriors you will find will just look at damage meters and stick it on the first person on there. Some argue that with the fact that once you have initial aggro, a boss pretty much sticks to you, so putting it on a Hunter or Rogue (that usually tops meters) would be a waste as they'll be redirecting threat to you anyway, and put it on a raging Fury Warrior.
Some switch it around all the time, and change to people like Boomkins, Mages and Warlocks for AoE, as no doubt they'll pick something up, then when it gets back to single target, go for high DPS. Personally, I like to see it on the other tank, especially if the Warrior is the OT. 3% damage mitigation isn't something that's going to save a DPS necessarily, and people shouldn't really be doing more TPS (threat per second) than the tanks.
Next one's a fairly easy one. Mages' Focus Magic (and I guess in turn Tricks of the Trade for Rogues). In raids this is usually rotated through the multiple Mages, or Rogues for theirs, in the raid. When there is only a single Mage, Focus Magic is best used on a class that crits a lot (No shit, huh?), so aim for Boomkins, SPs, Destrolocks, Ele Shamans (even Enhancement will do). As for Rogues, just use Tricks on any high DPSer that aren't in any danger of pulling aggro. Use it on tanks if they're slacking behind though.
Warlocks! Your Soul Stone is a powerful tool that, like a Druid's Rebirth covered by my last article, gives someone a second chance if they die in a fight. How it differs from a Druid's Rebirth is that instead of a reactive second chance, it's more proactive - you only get to cast it once per Warlock, and you can't cast it on someone who's already faceplanting the ground. This one's hard to have a definitive list of who should be top priority, as different encounters have different mechanics. Generally, I'd say a Druid (a DPS before a healing or tanking one) should get first priority, so they have the opportunity to jump back up and BR someone else and then get back into their role. Again with BR targets, please say when you're jumping back up. Makes life easier for healers to prep for it.
Ok... Well that post went on longer than I thought it would. Anyway, if there's anything I've missed, post it in the comments below!