User blog comment:Kirkburn/Technical Update: March 25, 2015/@comment-26479628-20150325202754/@comment-126761-20150325213810

I'd describe it as a combination of excellent user feedback (and there was a period of testing before the public beta), the big benefits it brings, and trying to develop smaller things, faster.

I must say a big thank you to everyone who's been trying it out :)