=== Designing a PvE spec from pure dps standpoint ===The following is a backbone of max-dps raiding spec:
8/0/47 for level 80, or
5/0/47 for level 70 (since at level 70 Inner Fire doesn't grant spellpower, Improved Inner Fire becomes useless). This leaves 16 free points at level 80, or 9 free points at level 70 (of those 3 points must be from Tiers 1-5 of Shadow tree, since the spec provided is uncomplete).
Talking about other DPS specs we have three variants: Holy + Shadow hybrid that stays outside of Shadowform and uses Smite as a filler (was actual in the middle of beta, when MF wasn't as overpowered as it's now), Disc + Holy classic holy dps build and deep Disc + Shadow build that reaches disc dps talents at the cost of missing some essential shadow talents. All of those are sub-par to a cookie-cutter one according to
Some more weird talent builds thread.
=== Picking manaregen talents ===The biggest deal here is get as little points in manaregen talents as possible, freeing some more space for utility/fun talents. Take a look at
Evaluating manaregen talents - it should help to pick up necessary manaregen abilities.
=== Utility/convenience talents ===* Improved Power Word: Fortitude (2 Ranks) -> adds 30% to PW:F effect when there are no more priests in the raid.
* Improved Power Word: Shield (2 Ranks) -> adds 30% to PW:S effect for a tiny buff to survivability.
* Improved Vampiric Embrace (2 Ranks) -> brings VE to 5% party heal and 25% self-heal.
* Shadow Focus (3 Ranks), Misery (3 Ranks) -> some points might be left out if you/your raid are close to hit cap (more info about hit caps in
Mechanics F.A.Q. thread).
* Dispersion (1 Rank) -> even in its current incarnation it's fun as hell, and useful for multiple purposes, my verdict: surely worth a single point.
* Blackout (5 Ranks), Improved Psychic Scream (2 Ranks), Silence (1 Ranks), Psychic Horror (2 Ranks) -> just to have some more teeth even in a PvE build.
=== Summary ===So the deal is to pick up as much dps talents as possible (currently even at level 70 it's possible to get all of those). After taking all the dps talents we can pick other talents, e.g. manaregen ones, or some fun/utility stuff. This partially depends on how you feel yourself mana-wise, but the rest is just a personal preference.
Some facts:
* Remaining points are not enough to reach neither DPS talents in Discipline, nor even Divine Spirit, so max tier of Discipline that is worth attention is Tier 3.
* Shadow Affinity seems unnecessary with the tanking changes / Shadowform aggro redux introduced in WotLK:
viewtopic.php?f=54&t=16974If you ask me, I like the following specs. You might like the others - feel free to post them here

* Lvl 80:
http://wotlk.wowhead.com/?talent=bVcbzhZZG0fVRfzfiqfzAo* Lvl 70:
http://wotlk.wowhead.com/?talent=bVZZG0fVRrzfiqfzAo