What's the current status in terms of UI design development?

I watched Brecht van Bommel’s UI analysis and challenges presentation from Blender Conference 2013 and was wondering what the state of the matter is now. There was also a presentation on this topic at the German Blender Day today but I learned about this event only two days ago so I couldn’t attend anymore. Would’ve been very interesting to me.

Could somebody summarise the progress that has or hasn’t been made in regards to UI (both in terms of the development process and actual implementations) since this conference two years ago for me? I’m fairly new to Blender and haven’t been actively following this (although I did watch Andrew Price’s UI suggestions at the time) but I’d be very interested to see what the state of UI development is at this point.
Is there an active and effective UI team now?
Is there a good process for decision making for design matters now?
Has there been a design philosophy and an overarching design guideline established which the development will strive towards?