I updated to 3.5.1 today on a network installation and all looked to be well. However, I'm seeing an issue in the admin panel. When I list all sites (/wp-admin/network/sites.php), and try to visit one of the network sites via the mouseover Visit link, the site folder is not appended to the url and I'm redirected instead to the root site.
Interestingly, some of the links work on the sites page. For example, edit site is:
However, the dashboard link does not work: example.com/wp-admin/
Anyone else having this issue?