@meshmarketer - Thanks for the thoughts. I checked the folder/file permissions. That didn't help me though. Not much you can do about a security roll-out. There're going to happen when they happen.
@krishna - Thank you for all of your help today on this too! I replaced all of the site files (including wp-login.php) with Wordpress 3.5.1, except the "/wp-content/" and the "wp-config.php". I also verified that the database was rolled back to "22441".
I've also flushed my cache and cookies, tried using incognito, and another browser.