Last night when I upgraded to WordPress 3.2 on a site we’re working on, I got a WSoD on the front end of the site after I logged in. I tracked down the source of the php error in the error log to a call to a missing method “WP_User” on the WP_User class. It turns out that the membership plugin from WPMUDEV was calling the WP_User class constructor in the older PHP4 style instead of the new PHP5 style. With the drop of PHP4 support in WOrdPress 3.2, this presented a problem. Luckily it was an easy fix. On line 23 of /wp-content/plugins/membership/membershipincludes/classes/class.membership.php, Change the following code from:
parent::WP_User( $id, $name );
parent::__construct( $id, $name );
Hope this helps!