I must say this one of the first threads i like. I mean i like how it started, will never know how it can end.
If you want a pvp disc build, it should be adapted to the kind of pvp go into. I mean it is kinda different if you go in battlegrounds, or arenas. If you go in arena it should be diferent to the arena type you will go more ( 1x1, 2x2, 3x3, 4x4, 5x5) and offcourse the classes you have as teammates.
Anyway advices are not what you asked, you asked for a build so i just build a spec that seems ok imo:
http://talent.mmo-champion.com/?prie...00000000000000
Take note that this is not the perfect build. So here are some opinions about bigger or smaller changes wich could be usefull
If you are going in arena with casters only you could go for Improved Divine Spirit.
If you consider you need more survivability you can go for Enlightenment.
Meditation can also be considered a good talent if you will consume mana to fast, Divine Spirit is also good for this.
A probabily strange talent could be Spirit of redemption + glyph of spirit of redemption, should be kinda of a strong combination but i dont know if it will work ok with melee teammates and if the other team is smart. The other team can go after a pillar, and if your mate(s) are melee they will either wait or go after them, out of your sight.
Anyway hope this will help you. Maybe a more experienced pvp disc priest will give an answer with a different build and some other explain.
Edit: Take note that the blizz can change the talent tree, so who knows what will be the talent tree at the release date
2nd Edit: build fixed with new priest changes(imp fort position switched with imp pw shield)