add_action( 'admin_menu', create_function( '$a', "remove_action( 'load-plugins.php', 'wp_update_plugins' );") );
add_action( 'admin_init', create_function( '$a', "remove_action( 'admin_init', 'wp_update_plugins' );"), 2 );
add_action( 'init', create_function( '$a', "remove_action( 'init', 'wp_update_plugins' );"), 2 );
add_filter( 'pre_option_update_plugins', create_function( '$a', "return null;" ) );
# 2.8 to 3.0:
remove_action( 'load-plugins.php', 'wp_update_plugins' );
remove_action( 'load-update.php', 'wp_update_plugins' );
remove_action( 'admin_init', '_maybe_update_plugins' );
remove_action( 'wp_update_plugins', 'wp_update_plugins' );
add_filter( 'pre_transient_update_plugins', create_function( '$a', "return null;" ) );
# 3.0:
remove_action( 'load-update-core.php', 'wp_update_plugins' );
add_filter( 'pre_site_transient_update_plugins', create_function( '$a', "return null;" ) );