Can't access sub-sites after WPMU update

I can reach my network admin area and the main site that I use, but for the 14 subsites that I created (on subdomains) I keep getting Fatal error: Call to a member function get() on a non-object in /home/user/public_html/wp-includes/query.php on line 27

The subsites are visible to the public, but I get that fatal error message whenever I try to access the dashboard as network admin. This problem seems to have come on sometime after I did a WPMU update in the network admin panel. But for the life of me, I can't remember which plugins they were.

Can you help?