when universe get changed,we do export the changed universe to  
enterprise server.user gets the view of changed classes
objects what ever we done at universe and already existed
objects which are not changed are viewed as same like before.

finding the changes by viewing the class name and objects
name which is get changed from old one.

Actually in BO whenever we create an universe automatically 
a document of the universe or the design structure with 
total number of classes and objects history which you can 
store a copy from the designer in any format and save it in 
your local server,comparing this way we can find out the 
newly added classes and objects

with out the notification from your side the end user 
doesn't know about the newly added classes and objects. 
first of all, the end user is not a technical person. so 
they are not having that much idea about that.

some end users might familiar in your universe. like if 
they are working with the universe frequently they might 
aware that how many classes and objects are exist in the 
old universe. so in case if you are adding classes and 
objects newly, that time the end users might ping you and 
asked about the details.