Just upgraded to Multisite WP 3.5 and all plugins. When opening the site, the page loads but the browser keep trying to load something. I’ve isolated it to the Avatars plugin. I deactivate it and the problem resolves. I deleted and re-installed. When asked to activate I said yes. Avatars (BBPress) activated, not (Multisite), but the browser resolved. Since I don’t run BBPress, I deactivated Avatars (BBPress) and activated Avatars Multisite. The browser again tries to resolve.