Addons can be a great help in many ways, from boosting your dps, warning you of boss abilities, keeping track of buffs/ cc's/ etc, to just helping keep track of all of your toons.
That being said, everyone's playstyle is different, and the amount of information each person can process at a given time is different. It is possible to have too many addons giving you too much information, just confusing the situation and distracting you from the primary purpose, killing the boss in front of you. Also, addons, no matter how small a footprint they have, do slow down the game speed and can affect framerates, especially on older or lower end computers.
With all of this in mind, the addons I will require for raiding will be kept to a minimum.
REQUIRED FOR ALL RAIDERS:
Deadly Boss Mods (DBM) and DBM: WotLK/BC/Vanilla
This is the only addon absolutely required for everyone in the raid, however there are others that are required/recommended depending on class and/or role
TANKS
Highly recommended: Tauntmaster - allows you to easily identify and taunt mobs you have lost control of
Recommend: Omen - threatmeter - in game threat meter is much better than it used to be, but omen is still useful
HEALERS
HIGHLY highly recommend: some form of healing addon like HealBot, I have seen some really good healers who do not use an addon, but they are very rare, and even they probably could have done better with HealBot
ANYONE WITH A CC
Required: something with a timer for your cc, like Mage Nuggets for any caster (mage, druid, shaman, lock) or serenity for hunters.
This is very important for you to be able to re-cc if necessary and to minimize your time off main target while doing so, thereby increasing your dps.
Specific classes
Boomkin - Balance power tacker - very helpful in managing your transitions from lunar to solar as well as your dots and other abilities, great dps helper
Hunter - Hunter Helper and Serenity - improved focus management bar, pop-up indication for boss abilities you can remove with tranq shot, cc timer, improved pet info (dont have a pet, pet dead, pet low health), warning if you are not in combat aspect, etc.
Mage - Mage mana bar - improved mana bar for mana management and when abilities proc, and indications for spell steal
Any class that has a dispell or buff removal (debuff removal for raid members, of buff from boss) should have some form of notification of when to use it, mage nuggets works well for spell steal, serentity for hunter tranq shot, healbot for such things as dispel magic, cure disease etc. If anyone knows of a good one for their specific class, let me know.
OTHER GENERAL ADDONS
Addon control panel (ACP) - adds an option to your game menu that lets you turn on/off addons without logging out (just a reloud ui) also lets you have specific addons on specific toons (ie balance power tracker on your boomkin, but not on mage where you have mage mana bar, etc.) Also if you run into frame rate issues, you can quickly turn off addons between fights in the raid. HIGHLY RECOMMENDED
Altoholic - Great for managing multiple toons, allows you to view/search all of your toons for items, including things in their bags/banks/guild banks, etc. provides warning for scheduled events on your calander on all your toons (even if the toon you are on isnt invited), tracks your cooldowns (truegold, dreamweave, transmutes, etc). Great overall addon if you run multiple toons, I couldnt live without it - HIGHLY RECOMMENDED
RangeDisplay - low footprint addon that provides range to target and range to mouse over items - usefull in staying out of aggro range, or to just get in range to cast - Recommended
Recount - not necessary, but nice to have, i run it and you can always ask me to post info
OTHER ADDONS I RUN (at least occasionally)
Ackis recipe list - scans your toon for recipes for professions and give list of those you do not have
Bartender4 - replaces/adds too standard interface bars, allowing you to customize extensively
Coordinates - gives a indication of the coordinates you are at
Friendshare - keeps your friends list/ignore list updated across all your toons
Quickmark - easy raid marking tool
Postal - mail management tool
Time to die - estimates when mob will die, usefull in determining whether it is worthwile to put a certain dot on or not, etc
I will also be using Afterlife - allowing me to track all cc timers, might be useful for tanks, i will try to announce when something will run out, but dont rely on me, each cc'er should be tracking their own cc timer
There are many, many other addons out there, some usefull for raid, others for just normal gameplay. If you have one you would like me to add, plese let me know.
[As posted by Ferret]
That being said, everyone's playstyle is different, and the amount of information each person can process at a given time is different. It is possible to have too many addons giving you too much information, just confusing the situation and distracting you from the primary purpose, killing the boss in front of you. Also, addons, no matter how small a footprint they have, do slow down the game speed and can affect framerates, especially on older or lower end computers.
With all of this in mind, the addons I will require for raiding will be kept to a minimum.
REQUIRED FOR ALL RAIDERS:
Deadly Boss Mods (DBM) and DBM: WotLK/BC/Vanilla
This is the only addon absolutely required for everyone in the raid, however there are others that are required/recommended depending on class and/or role
TANKS
Highly recommended: Tauntmaster - allows you to easily identify and taunt mobs you have lost control of
Recommend: Omen - threatmeter - in game threat meter is much better than it used to be, but omen is still useful
HEALERS
HIGHLY highly recommend: some form of healing addon like HealBot, I have seen some really good healers who do not use an addon, but they are very rare, and even they probably could have done better with HealBot
ANYONE WITH A CC
Required: something with a timer for your cc, like Mage Nuggets for any caster (mage, druid, shaman, lock) or serenity for hunters.
This is very important for you to be able to re-cc if necessary and to minimize your time off main target while doing so, thereby increasing your dps.
Specific classes
Boomkin - Balance power tacker - very helpful in managing your transitions from lunar to solar as well as your dots and other abilities, great dps helper
Hunter - Hunter Helper and Serenity - improved focus management bar, pop-up indication for boss abilities you can remove with tranq shot, cc timer, improved pet info (dont have a pet, pet dead, pet low health), warning if you are not in combat aspect, etc.
Mage - Mage mana bar - improved mana bar for mana management and when abilities proc, and indications for spell steal
Any class that has a dispell or buff removal (debuff removal for raid members, of buff from boss) should have some form of notification of when to use it, mage nuggets works well for spell steal, serentity for hunter tranq shot, healbot for such things as dispel magic, cure disease etc. If anyone knows of a good one for their specific class, let me know.
OTHER GENERAL ADDONS
Addon control panel (ACP) - adds an option to your game menu that lets you turn on/off addons without logging out (just a reloud ui) also lets you have specific addons on specific toons (ie balance power tracker on your boomkin, but not on mage where you have mage mana bar, etc.) Also if you run into frame rate issues, you can quickly turn off addons between fights in the raid. HIGHLY RECOMMENDED
Altoholic - Great for managing multiple toons, allows you to view/search all of your toons for items, including things in their bags/banks/guild banks, etc. provides warning for scheduled events on your calander on all your toons (even if the toon you are on isnt invited), tracks your cooldowns (truegold, dreamweave, transmutes, etc). Great overall addon if you run multiple toons, I couldnt live without it - HIGHLY RECOMMENDED
RangeDisplay - low footprint addon that provides range to target and range to mouse over items - usefull in staying out of aggro range, or to just get in range to cast - Recommended
Recount - not necessary, but nice to have, i run it and you can always ask me to post info
OTHER ADDONS I RUN (at least occasionally)
Ackis recipe list - scans your toon for recipes for professions and give list of those you do not have
Bartender4 - replaces/adds too standard interface bars, allowing you to customize extensively
Coordinates - gives a indication of the coordinates you are at
Friendshare - keeps your friends list/ignore list updated across all your toons
Quickmark - easy raid marking tool
Postal - mail management tool
Time to die - estimates when mob will die, usefull in determining whether it is worthwile to put a certain dot on or not, etc
I will also be using Afterlife - allowing me to track all cc timers, might be useful for tanks, i will try to announce when something will run out, but dont rely on me, each cc'er should be tracking their own cc timer
There are many, many other addons out there, some usefull for raid, others for just normal gameplay. If you have one you would like me to add, plese let me know.
[As posted by Ferret]