Rather a nice video on this guy's page showing the iPhone interface, and offering some praise and some critique. As to the user interface overhead added - what he calls "administrative debris" - I completely agree. On desktop GUIs the usual/unquestioned overhead includes titlebars, menubars, and scrollbars - all of which take large meaningless amounts of space on current screens (another case of design that made sense once, but much less so now). On the iPhone the Apple folk generally do a good job of minimizing UI overhead, with a couple exceptions.
At the end though he offers a replacement for the iPhone weather screen, and without a doubt his replacement is a very bad idea. The big/readable day and temperature information from the iPhone version is shrunk to a smaller much less readable size. A large portion of the screen is instead taken up by an animated image apparently from a weather satellite. While undoubtedly cool, the animation carries little useful information. When you are looking for information about future weather, an animated weather map showing the recent past is not especially helpful. All of which means he is using a larger portion of the (small) screen for the least useful information.
Using much-smaller-than-optimal font sizes is a common mistake in web and desktop user interface design. The problem is much more acute on small cell phone screens. Reading small characters may be very difficult in unfavorable light conditions. I can see allowing small fonts when web browsing - as this activity is more likely done while the user is indoors and stationary. For anything that might be used in less favorable conditions - like driving - you want to push up the font sizes and unclutter the screens. You want the user to capture relevant information in a single quick glance.
Which all leaves me in an odd position. This guy is a pretty well-known name (in some design circles). In part he is making a point - to a somewhat large audience - that very much needs to be made. On the other hand, he gets one part very badly wrong.
Oh well. This is pretty much all I can do.