Posted by Steve Faulkner on January 15, 2009;
WAI-ARIA Landmark Roles
The WAI ARIA specification defines a set of specialised “landmark” roles. These roles provide a method to programmatically identify commonly found sections of web page content in a consistent way. they can be used now in whatever flavour of (X)HTML you prefer. This allows assistive technologies to provide users with features which they can use to identify and navigate to sections of page content.
Full article at http://www.paciellogroup.com/blog/?p=106