Ton Roosendaal writes:
William has updated the paper he presented during the Blender Conference. He was very pleased with all feedback, which mostly was very positive. His update covers some of the criticism he received, and clarifies some unclear parts.
I think did a great job on this, it's a good analysis which will help us forward. Although it's important to review such proposals now, be aware that an actual implementation of a new UI is really not scheduled yet. However, the 2.5 event/tool refactor project does cover the foundation and back-end allowing UI concepts like this.