Is it support? That is an interesting question if you ask a Microsoft consulting company. You might just get a mixed bag of answers. The goal of a Microsoft consulting company is to push HyperV. Lync and Skype for Business are absolutely supported on VMware hypervisors. It falls under the “Server Virtualization Validation Program” from Microsoft. UC products like Skype and Lync do not fall under the same restrictions as Exchange when it comes to the storage platform. Microsoft will not support Exchange if it is on NFS storage (even though the same conditions for the restrictions exist in SMB3). There is no known restrictions on storage platform for Lync or Skype.
The design considerations in the “Planning a Lync Server 2013 Deployment on Virtual Servers” guide are all geared towards HyperV. VMware took up issues with this article (detailed here) and asked why Microsoft never created a validation document for VMware (clearly a market leader). To date, there still has not been a document published by Microsoft, and I do not expect them to publish a favorable article for a competing product. As far as designing your environment, do use the guidelines listed by Microsoft, but pay not attention to the restrictions on HyperThreading and memory sharing. There is not a good technical justification from Microsoft to disable these options when using VMware products.
I work in an environment where I have a multi pool global Skype deployment for 5,000 users and a US pool for 5,000 users all running on vSphere. I have not had any hypervisor related issues and I’ve never had issues with Microsoft support when it comes to having the platform on VMware products.
Don’t be persuaded that vSphere is not the best platform for Skype or Lync. I’ve heard comments like “so you’ve chosen the most expensive and complex product for your environment” or “you are not guaranteed to get support from Microsoft if you have issues in your environment”. That last statement would be somewhat true if the environment was poorly designed. Just make sure your design considerations fall within Microsoft guidelines.