There is a VMware KB1014508 article which helps you correlate build numbers of a product with the version number which could be useful. https://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1014508
VMware has just announced the way vSphere editions will be offered soon. Currently there are 6 SKU available which are: vSphere Standard vSphere Enterprise vSphere Enterprise Plus vSphere with Operations Management Standard vSphere with Operations Management Enterprise vSphere with Operations Management Enterprise Plus VMware will be reducing this down to 3 SKU which will be: vSphere Standard vSphere Enterprise Plus vSphere with Operations Management Enterprise Plus As you can see VMware has removed the following: vSphere Enterprise vSphere with Operations Management Standard vSphere with Operations Management Enterprise So what options do I have if I have one of the editions listed above? Existing customers with vSphere Enterprise who have a valid Support and Subscription (SnS) will be entitled to an optional upgrade to vSphere Enterprise Plus at 50% discount off the upgrade licence prices. This promotion is valid from 10th February 2016 to 25th June 2016.
VMware has opened up their vSphere Beta Program so it's time to register if you would like to see what is coming for vSphere. Being able to participate and possibly shape the outcoming of a product is always a plus. http://blogs.vmware.com/vsphere/2016/02/vsphere-beta-indicate-your-interest.html
There is a great VMware white paper around virtualising Domain Controllers which documents the best practices and steps on how to make the changes https://www.vmware.com/files/pdf/solutions/Virtualizing-Active-Directory-Domain-Services-on-VMware-vSphere.pdf