Input, Session and Cookie get's will return NULL.
Read more about this change here:
http://codeigniter.com/forums/viewthread/215833
diff --git a/user_guide_src/source/libraries/input.rst b/user_guide_src/source/libraries/input.rst
index 1f2ea65..432bac3 100644
--- a/user_guide_src/source/libraries/input.rst
+++ b/user_guide_src/source/libraries/input.rst
@@ -18,7 +18,7 @@
 :doc:`controller <../general/controllers>` is invoked. It does the
 following:
 
--  If $config['allow_get_array'] is FALSE(default is TRUE), destroys
+-  If $config['allow_get_array'] is FALSE (default is TRUE), destroys
    the global GET array.
 -  Destroys all global variables in the event register_globals is
    turned on.
@@ -53,14 +53,7 @@
 having to test whether an item exists first. In other words, normally
 you might do something like this::
 
-	if ( ! isset($_POST['something']))
-	{
-	    $something = FALSE;
-	}
-	else
-	{
-	    $something = $_POST['something'];
-	}
+	$something = isset($_POST['something']) ? $_POST['something'] : NULL;
 
 With CodeIgniter's built in functions you can simply do this::
 
@@ -95,7 +88,7 @@
 To return all POST items and pass them through the XSS filter set the
 first parameter NULL while setting the second parameter to boolean;
 
-The function returns FALSE (boolean) if there are no items in the POST.
+The function returns NULL if there are no items in the POST.
 
 ::
 
@@ -115,7 +108,7 @@
 To return all GET items and pass them through the XSS filter set the
 first parameter NULL while setting the second parameter to boolean;
 
-The function returns FALSE (boolean) if there are no items in the GET.
+The function returns NULL if there are no items in the GET.
 
 ::
 
@@ -210,7 +203,7 @@
 
 	cookie('some_cookie');
 
-The function returns FALSE (boolean) if the item you are attempting to
+The function returns NULL if the item you are attempting to
 retrieve does not exist.
 
 The second optional parameter lets you run the data through the XSS
diff --git a/user_guide_src/source/libraries/uri.rst b/user_guide_src/source/libraries/uri.rst
index ee60b77..cdd76e3 100644
--- a/user_guide_src/source/libraries/uri.rst
+++ b/user_guide_src/source/libraries/uri.rst
@@ -25,7 +25,7 @@
 #. metro
 #. crime_is_up
 
-By default the function returns FALSE (boolean) if the segment does not
+By default the function returns NULL if the segment does not
 exist. There is an optional second parameter that permits you to set
 your own default value if the segment is missing. For example, this
 would tell the function to return the number zero in the event of