Error after upgrading 4.6.6 to 4.6.8

I get this error whenever I view the forum and any commented node:

warning: Invalid argument supplied for foreach() in /home/.darnel/planetja/planetjazz.org/modules/node.module on line 358.

warning: implode(): Bad arguments. in /home/.darnel/planetja/planetjazz.org/modules/node.module on line 363.

user error: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '' at line 1
query: SELECT n.*, u.uid, u.name, u.picture, u.data FROM node n INNER JOIN users u ON u.uid = n.uid WHERE  in /home/.darnel/planetja/planetjazz.org/includes/database.mysql.inc on line 66.

warning: Cannot modify header information - headers already sent by (output started at /home/.darnel/planetja/planetjazz.org/includes/common.inc:384) in /home/.darnel/planetja/planetjazz.org/themes/planetjazz/page-forum.tpl.php on line 8.

I upgraded from 4.6.6 to 4.6.8. I noticed this just now. There were no upgrade errors.