Of all the tech blogs I read, thisismynext were the only ones who reported a laggy UI. Engadget and gizmodo reported the UI as very smooth. Next time get your fucking head out of apple's ass and take a look at reality.
That's not the fucking issue here. The only issue is whether is if ICS is smooth and yes it is across the board. But not in apps that havent been updated to take advantage of the newly added HW acceleration yet.