While we're talking about things we don't need, let's include this change.
The fact is, for most of the last two decades we've already had a UI where users who don't care to attend to the URL don't have to, and users who care to notice can. What does this add? Nothing. But it does take away some legibility for people who care, and discoverability for people who might learn to.
99% of people using web browsers really get no cues from the path? Cite please. URLs aren't high tech any more than the address to your house is, and my observation is that even non-developers who are simply experienced browsers pick up cues -- even from barely legible URLs mostly meant to be parsed by machines. You don't have to be a programmer to observe that typing a string in takes you to a page, or that the string changes when the browser loads a change, and put together the address correlation until you start to understand what a URL is without even really thinking about it.
Or at least, you wouldn't have to be a programmer to learn to make that connection based off of simple observation skills if we kept the current model. If we move to this new hide-the-URL UI, probably you would (self-fulfilling prophesy!).
And sure, the web has lots of URLs that don't provide a lot of easily parsed cues. In the interest of being a little less selective, though, let's look at a few others:
http://ask.metafilter.com/261148/Give-up-financial-stability...
https://www.google.com/search?q=percent+of+the+web+powered+b...
http://blog.ebay.com/ebay-inc-earnings-q12014-twitter-sessio...
https://twitter.com/paul_irish/
http://www.allenpike.com/2014/burying-the-url/
Do people need to see these things? Nope. Can they derive utility from being able to see them? Yes. And they do.