We find this talent really fun in the Holy play style. By chance. gives an extra instant Flash heal, helps with mana conservation and also reduces your Holy Word: Serenity through Holy Words. Great for dungeons especially if you find yourself Smiting to help the dps.
Surge of Light
Requires: Level 75
Your healing spells and Smite have a 8% chance to make your next Flash Heal instant and cost no mana. Stacks to 2.