Dave Winer is not right. Why would you want a browser to default to zoomed into an article on a web page? How would it know which one to bring up?
The cool part about the Safari browser in the iPhone is that it understand CSS blocks and knows how to isolate them in the browser view. Please don't confuse this with the ancient concept of "large fonts" in a browser. It's nice to see a web page and then double-tap to read one of the articles or view a picture. I wouldn't want to have to zoom out each time just to get my bearings.
After reading Walt Mossberg's review, I'm also convinced that many of the negative keyboard reviews will go away after a week or two.
There are certainly faults with the iPhone (this is a 1.0 device), but what we really need to focus on is the revolutionary software interface. This is a game changing technology that shouldn't be trivialized.