One of the major issues with the FamilySearch.org Family Tree has been and continues to be users of the Family Tree that make changes that are unneeded or inaccurate and have no contact information in the program. That situation is about to end. The Beta version of FamilySearch.org Family Tree now has a Messaging Feature. Here is a screenshot of the location of the notices from the direct messaging:
The link takes you to a list of your unread messages or also a page to view all the messages called the FamilySearch Mailbox.
This is a long anticipated and awaited development. Of course, it will not solve the problem of user who refuse either read or answer their mail, but it will provide a venue where communication can take place for those users who either do not have or refuse to disclose their email address.
If you find a change or addition and need to contact the user, there will be a link to send a message on the info pop-up that will also have their name, email if disclosed and other contact information. Here is a example with the pertinent information fuzzed out.
I will be watching for the change to to be added to the FamilySearch.org website.