Almost after 3 months VMware has released vSphere 6.7 U1 an update for vCenter Server, version 6.7 U1b, has been released as of 2019-01-18.
This is a bug fix release and includes some critical fixes, including e.g:
If you remove a Virtual Machine (VM) folder from the inventory using the vSphere Client, formerly known as the HTML5 client, the action might delete all the VMs as well and not just the folder.
Some of the configured vCenter Server user permissions might be deleted/removed when the vpxd service is restarted. You might see the following message: Reason: No reason given
vCenter Server 6.5 U2d & U2e to vCenter Server 6.7 is NOT SUPPORTED
VMware vCenter Server 6.7 U1b Download
VMware vCenter Server 6.7 U1b Release Notes
VMware Product Interoperability Matrices
VMware Compatibility Guide
PS - Before starting to upgrade to a new version make sure you have verified that your environment, including all your hardware and software components is fully supported.