I like how that build looks Sjans, I see you have blackout in there, I have really no experience with it yet, but I think it makes sense seeing it I can stun a mob, even if its at 6% that will give me enough time to get off another MB, or even a flay if they distance is right.
In PvP though I would worry about not having Shadow Focus, but I see the point in not having it cause Im not soloing +5, and if there are +5s around I am healing. not doing dmg. so it makes sense.
The only reason I took Shadow weaving is cause everyone says its such a great skill, but at my level Im not doing that much damage, I think my highest crit was around 700. but I also fight mobs that are -1 or -2, and I often see myself trying to get 5 shadow weaving, but by that time I'm wanding the mob cause its at 30% and my SW:P is also ticking away. maybe if they didn't nerf it and it was about to do 1% more damage when fully stacked it would be nice in boss fights... but even then I rarely get to DPS unless there is another healer in the group and they say that I can DPS and they will take over healing for some time.
So I may respec to that build looks pretty solid, and I haven't had that much trouble healing so far with one set of gear, A lot of the other priest I come across have almost 800 less mana than I do and about 200 less HP. I do have to upgrade some of my gear in like 5 more levels, but with enchanting i am able to get a lil more wear outta my gear.