Index: src/wp-signup.php
===================================================================
--- src/wp-signup.php	(revision 26979)
+++ src/wp-signup.php	(working copy)
@@ -232,12 +232,6 @@
 		$errors = new WP_Error();
 	}
 
-	$signup_defaults = array(
-		'blogname'   => $blogname,
-		'blog_title' => $blog_title,
-		'errors'     => $errors
-	);
-
 	/**
 	 * Filter the default site sign-up variables.
 	 *
@@ -251,7 +245,11 @@
 	 *     @type array  $errors     An array possibly containing 'blogname' or 'blog_title' errors.
 	 * }
 	 */
-	$filtered_results = apply_filters( 'signup_another_blog_init', $signup_defaults );
+	$filtered_results = apply_filters( 'signup_another_blog_init', array(
+		'blogname'   => $blogname,
+		'blog_title' => $blog_title,
+		'errors'     => $errors
+	) );
 
 	$blogname = $filtered_results['blogname'];
 	$blog_title = $filtered_results['blog_title'];
@@ -324,20 +322,25 @@
 
 	$public = (int) $_POST['blog_public'];
 
-	$blog_meta_defaults = array(
-		'lang_id' => 1,
-		'public'  => $public
-	);
-
 	/**
 	 * Filter the new site meta variables.
 	 *
 	 * @since MU
 	 * @deprecated 3.0.0 Use the 'add_signup_meta' filter instead.
 	 *
-	 * @param array $blog_meta_defaults An array of default blog meta variables.
+	 * @param array $blog_meta_defaults {
+	 *     An array of default site meta variables.
+	 *
+	 *     @type int      $lang_id The language ID.
+	 *     @type int|bool $public  Whether search engines should be discouraged from indexing
+	 *                             the site. 1 for true, 0 for false.
+	 * }
 	 */
-	$meta = apply_filters( 'signup_create_blog_meta', $blog_meta_defaults );
+	$meta = apply_filters( 'signup_create_blog_meta', array(
+		'lang_id' => 1,
+		'public'  => $public
+	) );
+
 	/**
 	 * Filter the new default site meta variables.
 	 *
@@ -346,8 +349,9 @@
 	 * @param array $meta {
 	 *     An array of default site meta variables.
 	 *
-	 *     @type int $lang_id     The language ID.
-	 *     @type int $blog_public Whether search engines should be discouraged from indexing the site. 1 for true, 0 for false.
+	 *     @type int      $lang_id     The language ID.
+	 *     @type int|bool $blog_public Whether search engines should be discouraged from indexing
+	 *                                 the site. 1 for true, 0 for false. Default 1|true.
 	 * }
 	 */
 	$meta = apply_filters( 'add_signup_meta', $meta );
@@ -388,7 +392,6 @@
  *
  * @since MU
  *
- * @uses apply_filters() filter $filtered_results
  * @uses show_user_form() to display the user registration form
  * @param string $user_name The username
  * @param string $user_email The user's email
@@ -402,12 +405,6 @@
 
 	$signup_for = isset( $_POST[ 'signup_for' ] ) ? esc_html( $_POST[ 'signup_for' ] ) : 'blog';
 
-	$signup_user_defaults = array(
-		'user_name'  => $user_name,
-		'user_email' => $user_email,
-		'errors'     => $errors,
-	);
-
 	/**
 	 * Filter the default user variables used on the user sign-up form.
 	 *
@@ -421,7 +418,12 @@
 	 *     @type array  $errors     An array of possible errors relevant to the sign-up user.
 	 * }
 	 */
-	$filtered_results = apply_filters( 'signup_user_init', $signup_user_defaults );
+	$filtered_results = apply_filters( 'signup_user_init', array(
+		'user_name'  => $user_name,
+		'user_email' => $user_email,
+		'errors'     => $errors,
+	) );
+
 	$user_name = $filtered_results['user_name'];
 	$user_email = $filtered_results['user_email'];
 	$errors = $filtered_results['errors'];
@@ -511,7 +513,6 @@
  *
  * @since MU
  *
- * @uses apply_filters() to filter $filtered_results
  * @uses show_blog_form() to display the blog signup form
  * @param string $user_name The username
  * @param string $user_email The user's email address
@@ -523,14 +524,6 @@
 	if ( !is_wp_error($errors) )
 		$errors = new WP_Error();
 
-	$signup_blog_defaults = array(
-		'user_name'  => $user_name,
-		'user_email' => $user_email,
-		'blogname'   => $blogname,
-		'blog_title' => $blog_title,
-		'errors'     => $errors
-	);
-
 	/**
 	 * Filter the default site creation variables for the site sign-up form.
 	 *
@@ -539,14 +532,21 @@
 	 * @param array $signup_blog_defaults {
 	 *     An array of default site creation variables.
 	 *
-	 *     @type string $user_name  The user username.
-	 *     @type string $user_email The user email address.
+	 *     @type string $user_name  Username.
+	 *     @type string $user_email User email address.
 	 *     @type string $blogname   The blogname.
 	 *     @type string $blog_title The title of the site.
-	 *     @type array  $errors     An array of possible errors relevant to new site creation variables.
+	 *     @type array  $errors     An array of possible errors relevant to new site
+	 *                              creation variables.
 	 * }
 	 */
-	$filtered_results = apply_filters( 'signup_blog_init', $signup_blog_defaults );
+	$filtered_results = apply_filters( 'signup_blog_init', array(
+		'user_name'  => $user_name,
+		'user_email' => $user_email,
+		'blogname'   => $blogname,
+		'blog_title' => $blog_title,
+		'errors'     => $errors
+	) );
 
 	$user_name = $filtered_results['user_name'];
 	$user_email = $filtered_results['user_email'];
@@ -578,7 +578,6 @@
  *
  * @uses wpmu_validate_user_signup() to retrieve an array of the new user data and errors
  * @uses wpmu_validate_blog_signup() to retrieve an array of the new site data and errors
- * @uses apply_filters() to make signup $meta filterable
  * @uses signup_user() to signup a new user
  * @uses signup_blog() to signup a the new user to a new site
  * @return bool True if the site signup was validated, false if error