I use both Android and iOS for a considerable part of my day. On the Android side I roll with a Galaxy S3, Nexus 4 and Nexus 7.

It has gotten much better, most certainly, via things like concurrent and partial garbage collections (and the improvements in the integer-units in the CPUs, simply brute forcing through these UI thread impediments), and other core improvements, but it's still most certainly behind iOS (where UI priority was a core architectural concern from day one).

Aside from a still not silky smooth experience, Android still has an endemic problem with completely non-responsive interactions -- you click or do something and everything just stops with absolutely no hints or feedback....and then three seconds later a result appears.