VR so far is very gaming centric and Apple as no interest in gaming.
To get framerates and image quality that don't cause motion sickness, VR needs very high end hardware. There is nothing from Apple that comes close to being able to drive decent VR.
VR seems to be the complete opposite of what Timmy's Apple stands for. So, it should be interesting to see what they come up with. Maybe a google-cardboard clone that takes 2 watches instead of a phone. People can't rave about how much better than 2 screen system is than google's one screen version.
I'd suspect the new Mac Pros are. When I boot my 6 core Mac Pro into Windows (on an external SSD in my case) I can toggle AMD's Crossfire to use both GPUs (BTW the drivers had to be made into a Frankenstein installation package using a combination of parts from Bootcamp and two Windows drivers to do this as the cards are special versions for Apple. The details of how to do this I found here on MR). I can get 90 frames per second in GTA V on my 27" Apple Thunderbolt display at 1920 x 1080 and +60 f.p.s. at full 2560 x 1440. OS X doesn't yet utilize both GPUs in this way, FCPro X uses one for computation but there is no reason Apple could not enable Crossfire for such things as VR in the future.
I admit this is a very expensive solution but dual GPUs could be brought to more Macs in the future.