Caching, visuals, animations.
The pre-rotation animation is gone (thank heavens). My guess is something went into that whole (pre)process meant to make transitions smoother, but wasn’t getting the job done.
mSafari is snappier. Especially in the rotation area, the new tab presentation is quicker.
The ‘Android stutter’ is gone. Especially in the app switcher.
It is Geekbenching higher.