For me, after closing some apps (like the browser) the home screens are not smooth for several seconds, I think in PR1.1 the period of stuttering after closing apps was clearly shorter. SMS scrolling is not smooth at all, contacts scrolling is however. Not totally sure how it was in PR1.1 though. Also some web pages seem to stutter a bit more, I think this is related to more aggressive pre-rendering and thus less checkerboard patterns.