WAIT UNTIL OCCULUS COMES OUT BEFORE CHOOSING .............. ANYTHING
it's a DK (Developers Kit) @ the moment
Overpriced
Poor resolution
Grunt required to drive the gear is way over normal spec
let the nerds, sponsored by work and rich kids play and naff it up before committing your money.......
Now is certainly not the time to buy a /dk2 (mine is on ebay if interested

) but........ overpriced it certainly was not..... IF you had gotten one when the time was right. I got one in July 2014 and considering the game changing experience I had had with it over the last 16 months, its cost was frankly a pittance.
to OP, I got a new psu 12 months ago, I thought 650w would be fine. I am regretting it now as I am considering SLI for VR. I would say 800W gold rated is a good baseline to consider. IF you are convinced you will never SLI, then 650w is ok, but, as I learned....... never say never.
I'm given to understand the GTX 970 should be sufficient for the Oculus consumer release.
AFAIK GTX 970 is the official minimum supported spec... I highly doubt it will be sufficient to play games at full bubble however. I have a GTX980 and fully expecting to be making compromises unless i replace it or SLI it.