As someone with a disability myself (fortunately not one that prevents me from accessing and using virtual worlds too much), these new systems are looking really useful.
Also, I have found that virtual worlds have helped me deal with the pain that I experience from my disability, it provides a distraction from the pain and allows me to escape it for a while.
It is because of these experiences, I want to encourage and enable people to access VW for therapeutic means, and these kinds of technology help people do so.