[Guide] Warlock Glyphs

[gherkin]

A guide to warlock glyphs.  Some will show up in multiple sections - this means that it is viable in each section it is included in.  If I missed one, or you feel it should be included in multiple sections, post.

Minor Glyphs - The only ones worth taking are Unending Breath and Drain Soul.  The rest are just horrible and personal flavor. 

[USELESS GLYPHS]
Why God, why....

Healthstone - This only affects you.  This is basically a subtle way of insulting your healers.  Siphon Life is better while solo/leveling and everything else is better everywhere else.
Soulstone - This is basically planning for failure.  Don't fail and this glyph is useless.
Shadowburn - Shadowburn does not hit hard enough, even with a crit, to justify a glyph slot.
Death Coil - It looks useful, but its not.
Chaos Bolt - 2 seconds off sounds amazing, but its not.  The other choices are just better.
Shadow Bolt - Mana is not an issue.
Succubus - This can be completely bypassed by playing smarter.

[LEVELING/GRINDING/SOLO GLYPHS]

Life Tap - The most important leveling glyph - directly converts spirit (easy to find) into spell power (not so easy to find, early on).
Corruption - You will be casting Corruption a lot - instant Shadow Bolts are very useful
Felguard - If you use the Felguard to level, this is the best glyph you can get
Siphon Life - Paired with Life Tap, this makes 30+ a breeze.
Voidwalker - If you enjoy soloing instances, this is a must have in the harder content.
Health Funnel - Keep your pet alive while it tanks something and you have adds slowly dying on you.

[PVE GLYPHS]

Affliction:
Haunt, Lifetap, Curse of Agony produce the highest return on investment.

Do not use the following, for the reasons provided:
Corruption - Agony does more damage, too RNG
Unstable Affliction - PVP
Felhunter - PVP
Siphon Life - zero damage increase, insults your healers.

Demonology:
Metamorphosis, Lifetap, Felguard are the best. 
Replace Meta with Immolate for a 0/41/30 build, and Felguard with Conflag for a 0/40/31 build.

Do not use:
Agony - Everything else is better
Corruption - Everything else is better

Destruction:
Incinerate, Conflagrate, and Lifetap.

Do not use:
Immolate - Changes to the Lifetap glyph made Lifetap better.  This is still a good glyph, but not as good.
Imp - This would be our 5th choice - good glyph, just not good enough.


[PVP GLYPHS]

Curse of Exhaustion - This makes your snare range greater than the gap closer range of other classes. Kiting time.
Soul Link - This is a must have in order to survive.
Demonic Circle - Has its uses, especially against Rogues and Death Knights.
Fear - Not as useful as it once was.  Basically lets you do an extra 1000 damage before Fear breaks, which is a lot but at the same time isn't.
Felhunter - Affliction should take this as well as the extra healing is noticable.
Howl of Terror - Another good glyph.
Searing Pain - A decent glyph as this is your filler spell as Affliction. However, under 12% crit and this is useless.
Conflagrate - Sometimes you fight people who don't have dispel.  This is a direct damage boost against them.
Immolate - Useful to destruction to boost Conflag damage.
Unstable Affliction - Useful to get off a UA faster so it can't be interrupted as easily.
Life Tap - Useful for more damage, but the other options tend to be better.

[Kelpie]

Curse of Exhaustion is a must-have for PvP Affliction

[TerryBogard]

Curse of Exhaustion is a must-have for PvP Affliction

I disagree.... but then again I never liked having to spend talent points on it.

Edit: Its a personal preference for me. Probably is smart to take

[Nixia]

Isn't glyph of health funnel pretty useless? I mean the spell doesn't cost mana so its not an issue to recast it.

I know health funnel cost like an extra 100 hp the first second but thats not enought to make it worth a glyph slot imo.

[gherkin]

They changed it so it no longer can be pushed back. This is mildly useful to someone wanting to do lvl 70 heroics solo. I would deem this as not useless, as there will be times where you have to tank something while trying to heal your pet.