Not bad for a HTC phone..... j/p I'm just messing with you, I always felt the One X' ui was decently smooth like what you just showed me in your video, but what really sucked was the stock browser. Why don't you do a new video and show me how a webpage scrolls and pinch and zoom, or are you intentionally leaving it out because you know it would be choppy? Why don't you also do something in each of those random apps that you open and see how many you can open before the app restarts again?
Also the phone by itself looks smooth but if you put it side by side you will see a difference, just like how the super amoled hd screen looks fine by itself and looks worse as you put them side by side with a slcd2 screen. To some people they can see the faults of the smoled screen without putting it side by side ( I can't ) but I can certainly tell that this phone while smooth is not as smooth as the GS3 without it being side by side.