PUBLIC MARKS with tag Aria

Last but not least, we have also improved some of our accessibility features. The Overlay widget now prevents focus from going to other elements when set to "modal", InfoPanel has better ARIA support and the Slider widget has more intuitive keyboard access for screenreader users.

AJAX techniques have helped Web developers create live applications within Web browsers. The AxsJAX framework helps inject accessibility features into these applications so that users of adaptive technologies such as screen readers and self-voicing browsers experience the same level of interactivity that is now taken for granted by users of Web 2.0 applications.

by Rich Schwerdtfeger from IBM

The attribute describes the role(s) the current element plays in the context of the document. This can be used, for example, by applications and assistive technologies to determine the purpose of an element. This could allow a user to make informed decisions on which actions may be taken on an element and activate the selected action in a device independent way. It could also be used as a mechanism for annotating portions of a document in a domain specific way (e.g., a legal term taxonomy).

how you can improve the definition of what is what. Those roles are present into ARIA.

jARIA is a plugin for the jQuery javascript library that adds ARIA support to Web applications. It is based on a javascript library written for Mozilla by IBM.

it seems to be a good start

Bug 12132: Implement ARIA to enable dynamic web appliations