iPhone web application developer, Comoki, has unveiled a new, iPhone-compatible Wikipedia interface. It's not alone, of course, but joins the ranks of web applications like iPodia with some nice interface improvements. It has a more reliable "Save" feature and makes some nice formatting decisions on the page, including making bulleted lists collapsible. It also makes use of a little Ajax for zooming images without reloading the page, which you may or may not prefer to the more traditional approach. I did like the search-as-you-type feature on iPodia, which is currently lacking in Comoki's version.
Of course, you may prefer to go offline with something like wikipedia-iphone (Google Code). Or perhaps make use of an older iPod for such pursuits. Welcome to a wondrous era of unlimited access to questionable information of possibly-dubious origin. Good stuff.