What's new? Like any big improvements or software? Also where is this Google experience launcher?
Posted via Android Central App
The phone should be smoother, and there are a lot of awesome tweaks to the visuals (especially the transparent nav bar and notification bar). You get wireless printing, full screen mode for apps that support it, and many other subtle changes.
And here is the link for the Google Launcher, basically the same launcher used on the Nexus 5, making the phone look more like stock android. With KitKat, you get transparent bars.
I can't speak about the Z1s, but every other android phone that I have owned lost root when updating or the update failed.
My suggestion is that you un-root it, apply the update than redo the rooting process. Several folks on the XDA forums have reported success in rooting the Z1s post update.