Facebook is planning to make its messenger a standalone platform. This view could help in making sense of messenger.com
Also, they are going off xmpp or whatever its called. When they do, pidgin and other third party clients would no longer work.
This site would placate desktop users who don't want the full Facebook.com experience - users like me.
However, I don't like messenger.com and web.whatsapp.com because they waste my bandwidth. If they made use of chrome's offline app capabilities, I'd be happy.
