The familiar, troubleshooting tool used at times, has been removed from the 2013 OWA.
The About page in OWA 2010 gives a lot of information regarding the user connection, the CAS server/array, Mailbox server, POP & IMAP settings, version of Exchange servers, silverlight settings, authentication, S/MIME etc.
It is used as a “kind of” troubleshooting tool at times by the helpdesk. It also gives relevant info for an end user who is good with Exchange. It is no longer present in OWA 2013, neither in 2013 RTM or CU1.
I can understand that it takes time and resource to add new features, but why is the Exchange Team taking out features/options already there?