Our university is trying to get everyone moved to Office 365 and 
shutdown the few remaining departmental mail servers.   The following is 
the response I wrote to one of our faculty member who was unhappy about 
having his mail stored on servers in the US. There are substantial 
savings to universities in moving to Gmail or Office 365, especially as 
these services host your student population for free.

We're not just talking about an email solution -- the requirements are
for a facility with an integrated calendar, address book, mobile access
and collaboration features as well as email.  The only alternative to
Office 365 and Google Apps for Education that I am aware of is Zimbra.
There is an open source version of Zimbra, but most organizations would
want to purchase a commercial version which has more features.  There
are also third parties that provide a Zimbra hosted solution.

Who is using Zimbra?  Simon Fraser, Georgia Tech, Earlham College and
Carleton College are using it for everyone.  Texas A&M give faculty the
option of using Zimbra or Exchange.  The University of Pennsylvania uses
Zimbra for some of their users but they also have Exchange and Microsoft
Live.  Purdue University use Zimbra but some departments are on Exchange.

Are more universities moving to Zimbra?  Not as far as I can see.  I
have references to Bucknell, St. Olaf and Wheaton College having moved
off of Zimbra to either Office 365 or Google Apps.  Bucknell seemed
especially unhappy about their Zimbra experience as one of their IT
people described it as a disaster!  Texax A&M which are currently listed
on the Zimbra web site as a customer are dropping it.  Their IT Advisory
Committee decided last October that all email on campus should be moved
to either Office 365 or Google Apps. Their timeline is to have students
moved to the new service by August, 2014.  The topic of mail systems
comes up on three different mailing lists I subscribe to and there is
regular discussion of moving to Office 365 or Google Apps but no one
talks of moving to Zimbra (or anything else for that matter).