The idea behind the Holy "cast three in a row" talent (it's called "Chakra") is that we've always positioned Holy as a versatile healer. This talent lets you shift into different modes. If you need to be a tank healer, cast three single target heals and your single-target healing is now better. Cast three area heals, and you can be a temporarily specialized group healer. We're going to try to play this mechanic up with a cool UI to try to get that "I'm almost in the zone" feel. We'll let it apply to as many types of spells as we can, perhaps even Smite for those times when nobody's taking damage__________________
Lead Systems Designer
Source: WoW US Forum
Of course, nothing is confirmed yet, but I'm just thankful that at least they are thinking about it. It's probably done to ease up leveling as well as those i'm-bored-while-healing moments, but regardless, it's a cookie.