Every week, Spiritual Guidance will offer practical insight for priests of the holy profession. Your host today is Alex Ziebart who doesn't have as many cool links to plug up here as Matticus does but will try anyway. This week we get our Shadowform on..
PvE Shadow - Raiding
MMO-Champion has a great tool for setting up talent specs, because you can include your glyphs as well, so we're going to be using that. This spec (14/0/57) will be a fairly cookie-cutter raiding build in patch 3.1, with only very minor variations from person to person. The Shadow tree isn't a very complicated one. Either a talent boosts your DPS, or it does something else. For a raiding spec, you want all of the DPS talents and you can skip all of the 'something else' talents unless they're mandatory for a DPS talent. It's pretty straightforward. Even in the Discipline tree the ultimate goal is to pick up the DPS talents, Twin Disciplines and Improved Inner Fire. Meditation isn't a direct DPS talent, but having no mana is certainly a DPS hit.
Shadow Affinity is one talent that tends to grab people's eyes and seduce them into speccing it, but don't do it! Shadowform already comes packaged with 30% threat reduction, so there are almost no situations in which you'll need Shadow Affinity in PvE as well. None of the Ulduar bosses we've seen so far will cause a Shadow Priest threat problems unless your tank isn't sure how to push his buttons. You definitely do not need two threat reduction talents, and the new dispel component of Shadow Affinity is a PvP thing, not a raiding thing.
Glyphs, too, are pretty straightforward for Shadow. As a raider, your Major Glyphs should be Glyph of Shadow, Glyph of Shadow Word: Pain, and Glyph of Mind Flay. Your minors aren't very important, but I'm personally going to try to keep Glyph of Shadowfiend in there no matter what spec I am. Having a little insurance is pretty nice.
PvE Shadow - Non-Raiding
A non-raiding spec for PvE is going to vary a lot from person to person. The Shadow tree is what you could call bloated, but it's the good kind of bloated, not the bad kind of bloated. Almost every single talent in the tree has a use, so you get stuck deciding which ones work best for you personally. I would use a build like this one (9/0/62) if I'm just questing and doing 5-mans, but don't worry about copying it exactly. You don't need to do thatm, and probably shouldn't do that. Tailor it to what works for you. As long as most of your talent points are in the Shadow tree, you can probably end up with a passable spec.
Glyphs aren't quite as varied, there are still only a few that you would really want to use. Avoid the Glyph of Mind Flay this time around, because you don't wan't to give up the snare if you're just questing around. I replaced it with a Glyph of Dispersion, because a lower cooldown on it will reduce downtime (especially with the loss of Meditation to get all I want in the Shadow tree) and let me solo ridiculous, absurd things I shouldn't be able to solo more often! Glyph of Shadow and Glyph of Shadow Word: Pain still take up my other two slots. The other options simply aren't worthwhile in PvE.
Shadow is a very easy talent tree to pick apart. There aren't many useless talents. As I said, spending talent points is largely going to come down to what is best for you. A raiding spec is a little more cookie cutter, but you still have some freedom with it. Try things out, experiment, do some reading, find what you like. Use what I've given you as a framework. Don't take it as an absolute.
Want to find more great tips for carrying out your Priestly duties? Spiritual Guidance has you covered with all there is to know! And don't forget to check out our other Leveling Guides as well as our Wrath Guides and Galleries!