Oh? I just tried to get one with the instructions on their github page, and it said the box type was vbox. Are the vmware versions kept elsewhere?
Also, I think you can just make a directory in the `~/vagrant.d/boxes/coreos` folder called "vmware" and copy over the vagrant file, box.ovf and the metadata.json. Then you just edit the metadata to have a vmware provider and the box.ovf to reference "../virtualbox/<<theimage>>"
I however do not have a vagrant vmware license and cannot test this theory.