I don't see why we need DNS any more. Who types URLs in these days? The search engines can find your content and serve it up via IP address.
So when you want to put up a new website, you start the server and wait three days before the search engine crawls it... oh, wait, you'll need to link to it from another page and wait three days for the search engine to crawl that page... Ignore that problem for now. Assume that all the search engines will accept requests to immediately crawl your IP address. Your website is really generic at this point (ipse lorem and all that) so it's on the 10,000,000 page of any search term you can think of. Really hard to test. So what do you do? You somehow create a unique identifier and have the search engine crawl the site again. Now it's on top of the search! Are you feeling lucky? Of course you are, you've just invented DNS!
How many Bavarian Illuminati does it take to screw in a lightbulb? Three: one to screw it in, and one to confuse the issue.