Windows Phone is now a very fast growing mobile OS. The main reason for this is that gaps between apps of Windows Phone and other popular OS like Android and iOS is decreasing at a very good pace. Recently Russian blogger Eldar Murtazin leaked something really interesting about Upcoming Windows Phone version, Windows Phone 9.
Windows phone 9 (2014 3-4q) have another UI. That's not tales. I repeat – Microsoft change UI from Metro style…
— Eldar Murtazin (@eldarmurtazin) December 12, 2013
He said on twitter that Windows Phone 9 will launch somewhere in second half of 2014 and it will not have Metro UI anymore. Windows introduced the metro UI in Windows 8 as well, so it may be possible that Windows might discontinue Metro UI for its desktop operating system as well. Moreover Microsoft will discontinue Windows RT and will combine it with Windows Phone so both phones and tablets will be running same operating system. Just like Apple has same operating system iOS for both of its phones and tablets. This was already suggested in a post that Microsoft will combine Windows RT and Windows Phone into one operating system by 2015.
https://twitter.com/kreativtek/statuses/411023242154229761
So it seems like Microsoft is moving in some other direction we hope for the best though.