Talent Specs
Holy (28/33/0)
This build is rather phased out thanks to the new discipline goodies, but if you want to try it go ahead. Obviously you can move some points from Mental Agility into Mental Strength depending on how much mana you have and personal preference. 1 point in inspiration is just for dispelling, another thing for them to take off.
Shadow Drain (19/0/42)
This build drops Shadow Power and instead focuses on slightly cheaper spells and imp mana burn. Great for mana burn teams and for long battles you can sit back and mana burn with VT/SW:P/VE on your main target.
Discipline (42/19/0)
This build gives you cheap greater heals with excellent survivability. You can always move 4 points from Silent Resolve into Enlightenment, mostly it's a matter of preference. I've been asked quite a bit by people about imp inner fire why I don't get it. Well it's simple really if you do the math imp inner fire gives you very little extra armor (something like 300) and there is a lot of better talents to get. Again on reflective shield, it's nice but breaking cc is lame. Even if it rarely happens I'd rather not lose games because the warrior's deep wound is keeping him from being sheeped. This is the most prevalent for healing priests at the momment.
Shadow Burst DPS (15/0/46)
This build is good for a 4 dps set up. Shadow Power is what this build centers around going for huge mind blast/SW crits. If you can't drop targets early this build doesn't offer much in the way of long battles so be wary.
Disc/Shadow (34/5/22)
This is an interesting build in that it lets you run with a VE/Pain on the main target for bonus healing and a silence as well as a lot of the core disc/holy talents. Obviously you can't expect to be DPSing too much but with the bonuses to spell damage you can definitely help with that little extra burst.