Fairly simple, with the change to Mind Sear in cataclysm, you can now target both a friendly and an enemy.
Exploit:
Two aoe bubbles appear (one on self, one on friendly target) and will knock a person out of stealth.
Strategy that my priest partner uses:
Cast it on self, interrupts self after one tick, then casts full duration of Mind Sear on the friendly target. Repeat
Downside is you have to cast it on yourself every other time it is casted