iPad screen's aspect ratio consideration

A month ago John Gruber, author of the Daring Fireball blog, posted on twitter: “Shouldn't the iPhone shoot 16:9 video? Who wants 4:3 video nowadays?”

Many people admit that they expect all screens to be closer to 16:9 aspect ratio. However from the first look it is obvious that iPad does not have 16:9 screen. We can see from the picture above the iPad screen is apparently equivalent in its aspect ratio to 2 iPhone screens, stacked in landscape mode, which is 4:3. It is primarily meant to be used in portrait mode, and it looks like a video playback is a secondary function. Indeed a 16:9 video looks a bit skinny on the iPad.

So will 4:3 video get back to business or it is just another feature of more comfortable e-book reading?