tedster - 3:38 pm on Apr 21, 2010 (gmt 0)
There are a large number of potential canonical issues beyond the "www". See:
1. Canonical URL Issues - including some new ones [webmasterworld.com] for a discussion
2. Guide to fixing duplicate content & URL issues on Apache [webmasterworld.com] - the result iof jdMorgan's masterful research.
Google seems to handle the closing slash issue pretty well on its own these days. Still, it is a best practice to include that final slash. Interesting that the site: operator gives slightly different results for the two variations. The site: operator numbers have been whack-o for a while in other ways, but I hadn't noticed this variant.