Redirection is a very popular WordPress plugin, so I imagine this will be patched and released soon to be compatible with the latest WordPress 3.5 release.
The Redirection plugin still functions correctly and does work. However you should definitely patch this right away because it could be a potential SQL injection vulnerability.
You will see this error at the top of the Redirection plugin admin page:
Warning: Missing argument 2 for wpdb::prepare(), called in /public_html/wp-content/plugins/redirection/models/group.php on line 70 and defined in /public_html/wp-includes/wp-db.php on line 990
To fix the wpdb::prepare missing arguments error, simply:
Open /wp-content/plugins/redirection/models/group.php and find line 70.
$wpdb->query and save your changes.
You’re all done. Easy as pie.
Andrew Nacin explains why the change is necessary, so if you would like to read more about it check out the PHP Warning: Missing argument 2 for wpdb::prepare() post.
Andy Stratton explains in a comment why removing the entire prepare call is better than replacing with query.
Gist showing proposed changes is located HERE.