i havnt really used it a LOT, but so far in 5 mans its basically pretty worthless.
i have to say though that the other talents in holy are very nice. serendipity is nice, imp holy concentration is ok in the fact that you get more chance to CC, but it sucks that its really situational. twin disciplines in disc is nice for your prayer of mending, circle of healing, and renew.
desperate prayer is meh because its a nice heal that is instant, but it costs like a ton of mana.
test of faith is kind of a loser talent because you should have everyone topped off... and so far its not been too hard for me to do that in the current instance content *i am currently 76*
i know circle of healing is probably going to get the nerf bat which is really retarded, but if they do they need to give us a 51 point talent worth having.