There are definitely going to be some challenges to overcome with this, from both an Entropia Universe perspective and also Oculus Rift's perspective.
Having been mucking about with a DK2 in Elite: Dangerous, I can share that the experience, while thoroughly awesome, is currently fundamentally flawed.
Things that would need to happen:
1) In the first instance, at least 4K screens need to be utilised instead of the current HD units. To achieve the VR experience, a couple of lenses are utilised within the unit, which means that the pixel density becomes all too apparent.
2) nVidia specific issue, but nVidia graphics cards that have more than one GPU on one card will not support the OR in direct mode properly. The only way I can get the OR to work on said card is to run in Extended Desktop mode, this causes other issues, where the situation becomes a multi-desktop environment, and as such, the refresh rate of the OR can become limited to the refresh rate of the normally primary monitor, which is another problem, you have to make the Oculus primary when running in extended mode, which is a real ball-ache to deal with.
3) MindArk will need to do a lot of work with the HUD stuff, such as lifting it from the 3D elements but also making it possible to look around that plane. Again, the need for this harks back to the pixel density issue, which would be alleviated somewhat by using a 4K solution, but I don't believe the use of 4K screens will fix it 100%. Currently Far Cry 3 can be run under VorpX, but this is merely a hook-in solution, I wonder if MindArk are going down that road or looking to work in direct mode.
4) Textual based content rethink. Being able to read text is going to be one of the hardest challenges as once again pixel density causes us issues here. Colouring of the text can help a little, but not all the way.
5) Other: with the successful development of bendable screens, I would have thought an easier on the eye solution would be to utilise these screens and bin the lensing. I don't know of the ins-and-outs of how the OR works, but I think being able to use a lenseless solution would help alleviate VR Sickness.
Don't hold your breath for this guys, but this is a truly exciting prospect, whenever it happens.