Hi. I have been championing MM as a real replacement within the org I work for and really appreciate all the work you guys are doing at MMHQ!
The initial dev tests have been v.positive.
I'm now moving into rolling out a wider evaluation, to some of the key departments, that would have influence on MM's adoption.
1: I'd be keen to road test the enterprise version, as ldap integration would be key (as would voip integration)
2: I do agree with previous posts however, in that the open-source version, should ideally be able to leverage ldap, even if it was limited in scope (i.e. restricted to x number of objects and reduced filter/search).
I would certainly feel this would not impact MM enterprise pickup as more appropriate function, saml etc would still be required for the bigger players and surely, having many users on MM (even small open source players) would only open up MM as a real alternative to slack etc and have a much wider audience.
If it is possible, may I please request access to testing the enterprise version, so that at least during this next phase of testing, I can really test the value of MM as a real replacement to our current setup of Exchange, Lync and Slack leveraging our internal ldap (we have multi global ldap's).
I still love MM, would just love it a little more if it allowed some ldap functionality in the open source version 
Thx
Bry