Can we envisage a future where browsers won't have URL fields at all and search engines don't display URLs in their results?

In 1996 Tim Berners Lee wrote a paper outlining the main principles of how he felt website URLs should be constructed. One of these principles was something he called the Opacity Axiom. This is how he explained it:

The only thing you can use an identifier for is to refer to an object. When you are not dereferencing, you should not look at the contents of the URI string to gain other information. For the bulk of Web use, URIs are passed around without anyone looking at their internal contents, the content of the string itself. This is known as the opacity. Software should be made to treat URIs as generally as possible, to allow the most reuse of existing or future schemes.

What that means is that a URL doesn't (and indeed shouldn't) provide any descriptive information about the site it's pointing to. While that has some clear advantages of the kind Berners-Lee described, it also had the overwhelming drawback that it produced URLs (often based on database strings) that most users find very difficult to understand but still have to interact with. In 1999, the usability specialist Jakob Nielsen, wrote an article that directly contradicted Berners-Lee, stating that URLs are part of a website user interface and that they should accordingly be memorable, short, easy to type, provide a clear illustration of the site structure and should be 'hackable' (i.e. it should allow users to move to higher levels of the information architecture by deleting the end of the URL). Nielsen didn't call his article 'The Transparency Axiom', but he might as well have. Nielsen also made a prediction in the article, that URLs would ultimately prove to have a finite lifespan, noting in an update posted in 2005 that users were increasingly tending to type a company/website name into a search engine, rather than trying to guess the URL. A subsequent update, in 2007, noted that eyetracking studies had found people only spending 24% of their gaze time looking at the URLs in search results.

In 2011, it's probably reasonable to expect that percentage to have reduced even further. Google's breadcrumb rich snippet format now means that the URL won't even show up in search results at all; instead you get the site name and a representation of it's site structure, each level of which is selectable without any need to resort to the kind of hacking Nielsen was forced to recommend. At the same time, Google's Chrome browser has gone a lot further than its rivals in moving away from presenting URLs to the user. Where Firefox and Internet Explorer have separate fields for the URL and for searching, Chrome combines them so that you never need to enter a URL at all, but can instead just type keywords. This development is moving the web away from a command line interface and towards a search interface. Chrome has also completely removed the 'http' from the URLs it does present, and recommends in its SEO optimisation guide (PDF) that what's left should be simple to understand, descriptive and friendly to the end user (this sets Google firmly against Berners-Lee's Opacity Axiom).

All this makes me wonder whether Nielsen will be proved right and we can envisage a future where browsers won't have URL fields at all and search engines don't display URLs in their results.