I just want to add: vote is not very obvious - non internals people are getting too excited about this :P Please consider:
People that don't have an IDE that handles the imports automatically, will be effectively forced to prefix \ to everything, which is really ugly. But again, prefixing \ is not even the end of the world. I bet that if fallback to global scope didn't exist from the beginning, we wouldn't care anymore about prefixing \. PHP has tons of global symbols, it's not like other languages that have functions organized in classes. Doing the most basic array and string operations will easily require 4-5 imports, probably more. If all I had to do was `use String;` and all the string functions were available as methods on strings, then it would be completely fine. On the other hand, string functions are rarely used, and arrays can be replaced by oop collections like spl, ds, or even userland ones. Function autoloading is almost a development feature only, since in a few years we'll all likely use opcache, which doesn't need autoloading.
