I think the best solution would be a widely accepted standard of a single API to be used by game developers, so that they could cut down on development time. Then the people who make head tracking software would have to come up with someting that complies to this standard, or make sure their own API can interface with or "plug into" the game developer's implementation.
This not only makes it easier and faster for developers to code stuff, it also streamlines production of further titles and makes sure that everyone who wants to develop a head-tracking solution has a chance at making something work.
Some will say that NP will lobby against this and it could be true, but the bottom line is they couldn't roll it back if it started. Just imagine it, SoW, DCS A-10, the next ArmA title all come out with the same head-tracking API and demand the developers of head-tracking software and devices to conform with it, instead of vice versa where the developer has to do the work. If NP doesn't do it, they'll have a whole lot of angry customers, so they will be forced to
