Hi
I'm running 3.6.4 and did the WP 3.1 upgrade on a shared Windows server. This produced an infinite redirect loop error when accessing the home page. It is suggested that the solution is to disable the canonical redirects which are the real culprit behind the redirect loop.
Solution 1.
Use this plugin:
http://wordpress.org/extend/plugins/...edirects-pack/
I did and it worked.
Solution 2, maybe?
Add this to the theme function file:
remove_filter('template_redirect', 'redirect_canonical');