The first GDR update for 2014 is expected to come in June, which could be limited to bug fixes for Windows Phone 8.1. That would be followed with a larger update in the November/December period, similar in scope to the GDR 3 update that rolled out last year. And for those Windows Phone owners who suffer from slow carrier updates, a Developer Preview could be made available for those who register with Microsoft as a developer.
Following the two GDR updates, and perhaps a third one in early 2015, Microsoft will send out Windows Phone 9, which is code-named "Threshold". There is speculation that one of the updates will add support for a gesture-based 3D control system for the handset codenamed Goldfinger, due out in Q1 of 2015. And down the road, a Windows Phone update could turn on support for a dual-camera setup similar to what is on the back of the HTC One (M8).
Sounds like Microsoft is really on top of things as the tech titan tries to improve upon the strong momentum that the platform built up in 2013, when Kantar called it the fastest growing mobile OS on the planet.
source: WPCentral via WMPoweruser