DOCSP-22708 whats new v4.6 (#327)

* added whats new in v4.6

Author: kyuan-mongodb

source/whats-new.txt

@@ -12,8 +12,8 @@ What's New
 
 Learn what's new in:
 
-* :ref:`Version 4.4 <version-4.6>`
-* :ref:`Version 4.4 <version-4.5>`
+* :ref:`Version 4.6 <version-4.6>`
+* :ref:`Version 4.5 <version-4.5>`
 * :ref:`Version 4.4 <version-4.4>`
 * :ref:`Version 4.3 <version-4.3>`
 * :ref:`Version 4.2 <version-4.2>`
@@ -28,8 +28,12 @@ Learn what's new in:
 What's New in 4.6
 -----------------
 
-See `v4.6.0 Release Highlights <https://github.com/mongodb/node-mongodb-native/releases/tag/v4.6.0>`__
-on GitHub.
+New features of the 4.6 Node.js driver release include:
+
+- Improved the ``ChangeStreamDocument`` in TypeScript.
+- Even distribution of server selection based on load across servers.
+
+To learn more, see `v4.6.0 Release Highlights <https://github.com/mongodb/node-mongodb-native/releases/tag/v4.6.0>`__.
 
 .. _version-4.5: