There is a new Google search announced yesterday that will try to give higher rankings to pages that accommodate blind and visually impaired users.
Itís supposed to give higher rankings to pages that are simple and easily navigable by keyboard and comply with W3C guidelines. A quick look did not impress me - the sites that ranked well were not particularly good but not really spam either. I saw a high percentage of junk results like bizrate, craigslist and alibaba and the like. Odd that it doesnít seem to care much about 508 compliancy either.