iOS is not light years ahead of Windows Phone in basic fludity. Windows Phone is just as fluid. It's also ridiculous to say that Android is still a "bloated and laggy mess" with Jellybean. It's not remotely either of those. It has the occasional hiccup still but it's extremely fluid 95% of the time.
Yeah I didn't actually mean to include WP8 in that comment since it's not actually even competition. I haven't had extensive time with WP so I can't really judge it apart from their ecosystem.
I've had plenty of time with stock Jelly Bean on my GNex and it is still a laggy stuttery mess compared to iOS on the 4 or 4S.