Currently, Fade is meant solely as a PvE spell-- the only thing it does is within the priest's party, so it's useless both solo and in PvP. But Maxx of Jubei'Thos suggests buffing it to make it more viable across the board. Some players say it should, like Feign Death, "untarget" priests who activate it, but Blizzard says that's a no-no because it confuses players without indicating what's happening. Maxx's idea is even better-- make Fade cause magic and physical attacks against the priest to miss 50% of the time (kind of like a Rogue's Evasion).
For people who think that overpowers Fade too much, Maxx has a solution: Fade would also give a debuff. Either it would make the priest miss 50% of the time as well, or it could do something like an anti-shadowform-- nothing but healing spells while Fade is activated. I think it's an interesting idea, and it's worth a look by the devs at least-- Fade is useless in everything but PvE right now, and tweaking it a bit wouldn't hurt. A few priests, however, say there are too many problems already to be messing around with Fade, and I agree with that as well. Neth, fortunately, goes right down the middle-- she likes the Fade idea (and is passing it to the devs), and realizes there are issues with, say, Circle of Healing.
Especially with all the +healing to be found in Outland, Fade is losing its utility. It shouldn't be the first priority, but making it more useful would help the Priest class all around.