It's no surprise that Xin Zhao has been slated for a kit retooling. Being full of "all or nothing" style game play, low surviabiliy, and a heavy reliance on stick and hit have lead Riot to rework him and fit him into more viable spot. It's been a while since we've heard much about his kit rework/fix but Solcrushed assures us it is on the way and will be out "soon(tm)".
It's been a while since I gave an update on this.... so...the official forums.
He's close. I'm in the stage of balancing numbers on him now and barring setbacks he should be ready to go soon(tm) [but prob not real soon(tm)]
Keep the faith Xin fans! The end of the wait is near! (Crosses fingers)