What he mentions isn't fundamental, but half-baked, like not having bouncy scrolling or flicks or being laggy. Something can't be fundamentally broken if it can be fixed with a simple update in a few months. Other things he mentions are personal opinion (ie he doesn't like suretype very much) or are things present on the iPhone, for example:

"It can take two full seconds for the screen image to change when you turn it 90 degrees, three seconds for a program to appear, five seconds for a button-tap to register"

Take your iphone, open up contacts and count how many seconds it takes from the tap to being able to scroll or click. ~5s on mine, and I remember it being worse with OS 2.0. And what about switching orientations in ipod? At least a second unless it happens to get stuck and not rotate at all.

The difference here is one of perception. Apple loads their program IMAGE instantly, so it looks like things are going smoothly even when it's taking time. It was a smart move on their part.

Does rotating really have lag? It's pretty much instantaneous for me on a Touch running 2.1.