Glyphs are what personalizes your spec, and what highlights and builds upon its strengths. You should choose your glyphs not because they are what is "popular," but based on how useful they will be to YOU, in YOUR gaming situation.
- Swiftmend: Take this if you use Swiftmend at all.
- Wild Growth: Take this if you raid and find yourself using Wild Growth regularly. It can also be useful if you run lots of 5-man instances and almost always have lots of pets in the party who could use the 6th splash HoT, but remember that ranged players may be too far away to get the WG, so a 6th target per cast may not see much use in 5-mans even then.
- Nourish: Take this if you use nourish with any regularity. It will stack with 4pc T7 bonus. Don't bother with this glyph if you are not level 80.
- Lifebloom: Take this if you spend much time rolling lifebloom(s) on the tanks; it works well in tandem with the Nature's Splendor talent to maximize your lifebloom duration, giving you more time before having to spend the mana (and GCD) to renew it. It will increase the amount of time before it will grant the mana-restoring bloom heal effect, however, so if you regularly use lifebloom as a short-duration raid heal or rely at all on the bloom portion, this glyph may not be for you.
- Rejuvenation: Take this if your tank(s) spend a lot of time below 50% health AND you use rejuvenation as one of your most-cast heals. It can be even more useful if a good majority of your raid spends a lot of time at sub-50% health. It will not proc off of the 4-pc T8 bonus. This is a niche glyph, as most raids avoid letting their members sit below 50% health for any amount of time. EDIT: one such niche has been discovered for some players healing in hard-mode Ulduar25.
- Regrowth: Take this if you regularly reapply a regrowth before the HoT has worn off from a previous regrowth.
- Innervate: Take this if you have severe mana problems (for boosted self-innervates), or if you regularly give your innervate to someone else but could use a mana return off of it yourself. 3.1.2 Patch, Innervate is set to exactly 15,732 mana; this glyph will give you (the caster) an additional 3,146 mana with your innervates.
- Healing Touch: Take this if you want to emulate a paladin or are sub-80 (no nourish) and need a "flash heal," otherwise ignore it. Few druids go this route, but I *have* seen druids make good use of it at 80, in a 25-man lacking much in the way of MT healers. This glyph is built for MT-healer druids. Be aware that the Naturalist talent + this Glyph will give your HT a 1-second cast time unhasted, so it will ALWAYS either match or clip the Global Cooldown (which has a hard-set 1-second minimum time).
- Rebirth: Take this if you find yourself battle-ressing once every hour at least, often in situations of AoE splash damage (which might otherwise kill your freshly ressed buddy), and only if you don't think any of the other above glyphs would be more useful.
Minor glyphs are of far less importance.
- Unburdened Rebirth will save you a bag slot and money spent restocking on the reagent.
- Thorns decreases the number of times you have to reapply the buff on yourself, but how often are you getting hit to even make use of the damage?
- Wild will reduce the mana cost of your MotW/GotW buffs, which are usually cast out of combat.
- Aquatic Form: swim faster, pudgy seal!
- Dash: reduce the cooldown on Dash, if you find yourself needing to use it that often.