Docs - new default setting for createSession()

Author: jeffswartz

README.rst

@@ -184,6 +184,11 @@ This version of the SDK includes support for working with OpenTok 2.0 archives.
 work with OpenTok 1.0 archives.)
 
 The OpenTok.create_session() method now includes a media_mode parameter, instead of a p2p parameter.
+The default setting for the create_session() method is to create a session with the media mode set
+to relayed. In previous versions of the SDK, the default setting was to use the OpenTok Media Router
+(media mode set to routed). In a relayed session, clients will attempt to send streams directly
+between each other (peer-to-peer); if clients cannot connect due to firewall restrictions, the
+session uses the OpenTok TURN server to relay audio-video streams.
 
 For details, see the reference documentation at
 <http://www.tokbox.com/opentok/libraries/server/python/reference/index.html>.