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GlobalMax - 2:10 pm on Mar 9, 2011 (gmt 0)
I would go for site/page
[...]
As for last forward slash, the page should not have it as it denotes folder.
Here is the counter-argument (in favor of site/page/):
http://www.standardzilla.com/2007/07/09/dont-forget-your-trailing-slash/
I do use a trailing slash, even below the top-level. If provided with site/page, I 301 to site/page/.
Note, however, that I think of it more as site/topic/ than site/page/. URIs really indicate resources, not pages and folders.