I'd like to internationalize my site such that it's accessible in many languages. The language setting will be detected in the request data automatically, and can be overridden in the user's settings / stored in the session.
My question pertains to how I should display the various versions of the same page based upon language in terms of the pages' URL's. Let's say we're just looking at the index page of http://www.exampledotcom/, which defaults to English. Now if a French-speaker loads the index page, should I simply keep the URL as http://www.exampledotcom/, or should I have it redirect to http://www.exampledotcom/fr/?
I'm trying to figure out what benefits or consequences this has in terms of SEO. I don't want the French version of the site showing up in google.com if it prevents the English version of the same pages from showing up there, but I would like it to show up in google.fr.