This NY Times article describes the impact of the iPhone and other small-form factor Web surfing devices on the design of Web interfaces:
A quick trip to Web sites like Facebook, Twitter, Zillow or Powerset, all of which have been redesigned to take advantage of the iPhone, makes it clear that bigger is not necessarily better when it comes to exploring cyberspace. By stripping down the Web site interface to the most basic functions, site designers can focus the user’s attention and offer relevant information without distractions.
It’s obvious that reading a Facebook newsfeed or looking up the value of a friend’s home on Zillow doesn’t require a 20-inch computer display. It may also make more sense to keep the grocery list, play a game or read an online newspaper while mobile.
Moreover, a new wave of applications from companies like eBay, Bank of America and America Online that are designed for the second-generation iPhone 3G, which went on sale Friday, will further blur the line between the Web and the iPhone. The eBay application is available as a free download from Apple’s new “app store,” which is part of its iTunes service, and allows users to track auctions, place bids and flip through images of items for sale.
“By having fewer items to scan for on a small display, users can find what they want more quickly and can be more confident that they have made the right choice,” said Ben Shneiderman, a computer scientist who founded the Human-Computer Interaction Library at the University of Maryland. “If you just put the juicy stuff up there it works better.”
I will note that Shneiderman is a founding father of the user interface design community – I highly recommend his work, especially his book-length texts.