Fear lasted too long pre-nerf for locks because they could set up all their burst (demo) or heal up considerably (Aff).
Fear for Spriests should be used 8/10 times on another target rather than the one your attacking. If your that desperate, time it mid cast as an additional interrupt.
Oh and for the guy that suggested Mind Spike for some odd reason... It is singlehandedly the most useless ability handed to a class/spec for this expansion. With the changes to mastery and the wiping of DoTs, it serves absolutely no purpose.