The Accessibility settings icon is shown by default in gnome-shell. That is great!
However, there is no sane solution to turn it off for those who prefer less distractions and who have determined they don't need accessibility.

The only solution so far is to install a small extension that gets rid of it:
http://blog.fpmurphy.com/2011/04/gnome-3-shell-extensions.html (search for "Example 7")
Code is at http://www.fpmurphy.com/public/noa11y.tar.gz

While this works, it is neither user friendly, nor easy to discover. Please make that setting somehow configurable to be able to turn it off.

That might be a theme option, a magic gconf key, or a generic mechanism to turn off icons. But let me get rid of it in a sane way.