I think your build looks solid. If you are planning on dpsing more often than healing, especially in a raid, I think you'll be fine. Where I think you might struggle would be solo healing a long fight (heroics, for example). I'm sure it's do-able, it will just be a bit tougher.
It's interesting that you're looking at this build. I've seen a drastic decrease in the viability of healbot priests since TBC so far. I often wonder if I'd serve the guild better as a mana battery myself. I think there's probably a place for healbot priests...I'm just not sure where. It's really easy to find a place for a shadow priest, however. Priests used to be "the" premier healers (when played correctly, anyway) so it made the price of being gimped for everything else ok. If mana regen didn't exist through shadow spec, I'm fairly sure we could drop the class altogether at this point and not miss much:( The state of the class really saddens me since TBC. I love healing, always have, probably always will. As it stands now, I can still keep the people I'm healing up (which is what counts), but at the cost of the raid being down a paladin, druid, or shaman : /
It's interesting that you're looking at this build. I've seen a drastic decrease in the viability of healbot priests since TBC so far. I often wonder if I'd serve the guild better as a mana battery myself. I think there's probably a place for healbot priests...I'm just not sure where. It's really easy to find a place for a shadow priest, however. Priests used to be "the" premier healers (when played correctly, anyway) so it made the price of being gimped for everything else ok. If mana regen didn't exist through shadow spec, I'm fairly sure we could drop the class altogether at this point and not miss much:( The state of the class really saddens me since TBC. I love healing, always have, probably always will. As it stands now, I can still keep the people I'm healing up (which is what counts), but at the cost of the raid being down a paladin, druid, or shaman : /