For $500 for the kit he mentions I'd be willing to give it a go. It's not that far out of reach when you consider the cost of tripple screen gaming or buying one large screen or even a projector. None of those could compete for immersion against a VR headset.
Edit: Looks like things have already kicked off ....
http://m.engadget.com/2012/08/01/ocu...-john-carmack/
Edit2: This thing looks like its about to really take off, watch the video ...
http://www.kickstarter.com/projects/...ently_launched