So first things first, this isn't a complaint thread about the nerfs. I barely play Yasuo, but seeing him nerfed so hard does make my heart hurt a little - As far as Lolking is accurate, he's already got a sub-45% win rate above Gold.
So @... uh, whoever: has consideration been placed on moving Yasuo's shield passive to his W instead? This way he won't get his shield level 1, and he won't be as ridiculous at trading at level 1/2 as he is now. I get that his current health nerf was meant to hit his early game already, but a health nerf would stick with him through the entire game, where moving his shield passive would probably only hurt him level 1/2 - which in my (Silver league) experience is when he can trade the most efficiently.
EDIT: I would even argue that it makes sense thematically. Since the active blocks damage already, it follows that it would have a passive that also blocks damage. As if he passively had... say, a wall. Of wind.
EDIT 2: I'm saying that I think his power curve, not his overall power, is the problem.