See here: http://www.corkrdo.ie/n20_cork_limerick ... uction.php
EDIT: See - http://www.corkrdo.ie/files/N20%20broch ... ptions.pdf for brochure
The idea is welcome and, in my view, should begin as soon as humanly possible. However - would it not make sense to construct such a motorway from Mitchelstown to Limerick instead, using the new M8? Geographically, it would make more sense, as the distance appears shorter.