As far as Im concerned, the feature that separates the Dolphin Browser from Safari and other iPhone browsers like Skyfire and Opera Mobile is the webzine feature.
This unique feature makes it easier to read content from your most visited sites in magazine format, so you can stay in touch with your various networking hunts, as well as keep up-to-date with blogs all in one place. In the morning, I would often click the WSJ column in Webzine while enjoy the morning coffee.
One suggestion I have for the iPhone version would be to expand the number of Webzine slots, even if it means scrolling or adding additional pages.