Deepfish uses the same 'real' web interface (where you point and zoom on regular pages, not custom mobile pages) much like Opera mobile or Safari on the iPhone.
In theory, this method is great as there's minimal compromise on what sites you can now visit on your phone. Unfortunately, I still find the whole panning/point/zoom process a bit tedious. But I guess that's the best they can currently do on such tiny screens. Even on the Wii though (which uses the same browsing technique, but on a much larger screen) it can be a bit tedious.
some time back TMV pointed out that Deepfish was available - a sweet new browser from MS for Windows Mobile. But MS immediately closed the beta. I noticed today, that if you go to their site (http://labs.live.com/deepfish/) and choose registration, it will say its closed beta - but there is a link "if you forgot your activation id". I put in my email (im not part of their beta, mind you) and i was sent a reg key and download link! As I write this, I activated and am using it. If you have a smartphone or pocketpc device you aught to check it out before MS realizes the hole.