Android has a severe problem with ListViews. There are many improvements (i.e. Contacts is pretty smooth), but it's not a consistently smooth device. If you're moving from Android 2.x over to 4.x, you'll be blown away. But if you've used the competition for any length of time and you value responsiveness and smoothness, then you may feel like throwing said Galaxy Nexus against a wall (I've come pretty close to it).
Intel actually conducted a study into the success of the iPad:
Intel: Windows 7 tablets can outperform iPad 2 | News | TechRadar
They basically reverse engineered the iPad user-experience and concluded that the success of the iDevices is largely thanks to two main attributes:
1. 15ms response time (compared to Android's 150ms+).
2. Consistent 60fps smoothness (compared to Androids erratic refresh rate which is up and down like a yo-yo).
Other experiments have been conducted which show (what some have termed) 'micro-lag' - the small 'lag' (if that's the right word for it) that occurs when the Dalvick Garbage Collector kicks in.
You've really gotta ask yourself why Android tablets are not selling well (
Android Tablets Not Selling as Well as Claimed - Yahoo! News) while Apple can't seem to make enough iPads. Could it be because of this issue? IMHO, I point the finger firmly at this issue and Google for burying their heads in the sand and pretending it doesn't exist. Android is synonymous with 'lag', and with good reason.
I'd like to point out that I am NOT a 'hater'!!! I have spent over