I wasn't sure how to name this thread since the name can't contain spoilers. No this isn't a who would win if they fought thread, it's a move vs. move thread, more precisely:
Rasenshuriken
VS.
Kirin
They both seem to have amazing destructive power. While i'd say Rasenshuriken seems to be the deadlier of the 2 ( i just can't see anything surviving after getting hit by that ) it doesn't have such a big area of effect as Kirin does which makes it alot easier to hit your opponent. Then again it does require the use of outside forces and we all know how unpredictable the weather can be
Finally i'd say Kirin is the superior jutsu not because of it's power but simply because it doesn't have any of the nasty side effects that come from the Rasenshuriken, but if we're talking of raw power then the prize goes to Naruto's jutsu.