Currently we are working on UIkit 3 (~80% done) and YOOtheme Pro (~65% done). We hope to have both ready in Autumn.
The plan is to bring YOOtheme Pro to Pagekit by the end of the year. We think, this will be huge for Pagekit because YOOtheme Pro is a powerful theme (or more a website builder with a real-time preview) and comes features like a page builder, a style customizer for UIkit, different header layouts, a comprehensive layout, style and element library including slideshows, accordions and so much more... You can try YOOtheme Pro here http://yootheme.com/pro/
We think, it's very important for Pagekit now to have great themes and extensions, like a page builder or a shopping cart. With YOOtheme Pro we are covering the themes, widgets and the page builder. We also hope that some great extensions will be created by the Pagekit community. For example, I heard several people are working on a shopping cart.