Beginning in August, the Xbox One controller will include Bluetooth ostensibly to connect to Windows 10 devices more easily. Since you can already stream your Xbox One to a Windows 10 device, I think the biggest draw to having Bluetooth in these controllers would be the ability to use them with other tablets and phones such as iOS and Android.

As an avid Xbox One gamer who streams most of my gameplay to an iMac with Windows 10 Bootcamp, as well as an owner of several iOS devices, I think this would be an awesome development!

I also have my Xbox set up to be accessed from anywhere with an internet connection, so if I could play my Xbox games on the go, I may very well not have time for iOS games anymore.