Note/warnings about production use edited per comments from @ERH.

source/release-notes/2.4.txt

@@ -51,10 +51,9 @@ Text Indexes
 .. note::
 
    The ``text`` index type is currently an experimental feature.
-   Interfaces and on-disk format may change in future releases. To use
-   ``text`` index, you need to enable it at run time. Do **not** enable
-   or use ``text`` indexes on production systems.
-
+   To use a ``text`` index, you need to enable it at run time or
+   startup.
+
 Background
 ``````````
 
@@ -114,8 +113,9 @@ indexes have the following limitations and behaviors:
 
 - a collection may only have a single ``text`` index at a time.
 
-.. important:: Do **not** enable or use ``text`` indexes on production
-   systems.
+.. warning:: 
+
+   Do **not** enable or use ``text`` indexes on production systems.
 
 .. May be worth including this: 
 
@@ -129,12 +129,13 @@ Test ``text`` Indexes
 
 The ``text`` index type is an experimental feature and you need to
 enable the feature before creating or accessing a text index.
-   
+
 To enable text indexes, issue the following command in the
 :program:`mongo` shell:
 
-.. important:: Do **not** enable or use ``text`` indexes on production
-   systems. 
+.. warning:: 
+
+   Do **not** enable or use ``text`` indexes on production systems. 
 
 .. code-block:: javascript