Posted by bowersox on August 21, 2012 at 5:02pm
Let's take a look at the Blocks and Layout initiative Prototypes to give feedback on the ways these new UIs can be implemented for Drupal 8.
Here is the latest Prototype:
http://groups.drupal.org/node/242403
(click "Add a Page" to get to the most important part of the UI, namely how to pick a layout for your page during the creation process)
My initial impression is that this approach can be easily accessible because it is forms-based. It does not use any drag-n-drop interaction at all.
Is that the right approach? If we have feedback, it's good to provide that early in the design cycle.
-Brandon

Comments
Fluid project
Another approach would be to actually use drag-n-drop and try to make that accessible. It is harder, but perhaps feasible.
Here is a link to the Fluid Project Demos (try out the Layout ReOrderer Demo):
http://fluidproject.org/releases/1.4/demos/index.html
The Fluid Project is trying to make accessible, reusable javascript libraries for common UI needs like this. Based on their demo, it seems to me that their model for keyboard accessibility is assigning keystrokes to trigger events to move items. It doesn't look like they've tried to do any HTML5 drag-n-drop.
-Brandon
www.pixotech.com