That is indeed the case. Otherwise you can buy licenses meant for ISPs and cloud-hosting providers. Your "personal use of multiple VMs" is simply not contemplated. You could probably get by with a MSDN subscription, which gives you some leeway.
Edit: sounds like pretty much whatever you want.
http://stackoverflow.com/questions/584162/what-is-the-window...
http://www.itassetmanagement.net/2011/05/31/msdn-subscriptio... : there is a lot of fractal madness in this. "This applies to virtual machines as well – so if even one application on one virtual machine hosted on a physical server is used for production purposes, then ALL the virtual machines AND the physical host must be licensed as if they were production machines."
"Training is NOT considered a development activity, so all those being trained and the machines used for the training must be licensed appropriately." may be one of the reasons nobody ever gets any training in this business.