Nothing worng with holy/disc these days and while shadow has always been better DPS, disc/holy is far better equiped to deal with unexpected surprises. So yes I spend more time killing things but I never ever have to do a corpse run.

It's funny. That's exactly the build I'm using for grinding atm (and will be using through Wrath to level). As long as you have mobs to kill with that build, you don't run out of mana and get a huge boost to Spellpower (between Spirit Tap & Spiritual Guidance).

That build is very similar to what I have now, too (although it seems a little odd not to take Power Infusion when you're 31+ deep into Discipline).

I've been knocking over loads of quests lately to finish off the Loremaster of Outland achievement (I skipped heaps going straight from levelling to raiding). I've found it to be a very effective build, having no trouble soloing a lot of group quests recommended for 2-3 players, and zero mana problems on the grindiest of grind quests.

I expect it to be great for levelling from 70 to 80, effective solo, and with enough healing power to make instance healing trivial if I do some as I level.

okay..one more improvement, you should be able to heal 5 mans even better...

http://www.wowhead.com/?talent=bVcRzhxubxZfxt0cbqZh

I didn't take PI, because the boost in spell power with improved divine spirit seems kind of insane. Also note, i did the improved inner fire because at 71, it'll give a spell power bonus.

nice! Hadn't thought of that one, I'll have to try it out.