Video player functionality aside (I understand the complaints), that thing full-screened just feels like a native app.
You mean when they were using silverlight or now when they are using HTML5?
Is it only for mobile? I didn't see any "mob" or something in the URL. Anyway, with regards to being indistinguishable from native, I guess there is nothing quite like being reminded that you are "native" than an app complaining that you are on the wrong native device. :-)
In Firefox (my default br.) the message is: "Youtube on TV is not supported on this device, for more info go to: www.youtube.com/devicepartners" which is unclickable and unselectable. Modern web...