A summary of the changes already implemented are available here.

For accessibility purposes, these are:

Positioning of text and UI controls. No longer hard-wired to show the option, then the control, the author can set a question's preferences to indicate where the control should appear.

Shortcut key list during a test. The previous version only displayed the shortcut keys at the start of the assessment. The new functionality presents a link to the shortcut keys (which can be tabbed to). There is a request for this table to also be made visible using a shortcut key such as CTRL-K.