Despite being competitors, they aren't "direct" competitors. Rift doesn't work on PS4, Morpheus won't work on PCs. If you play on PS4, get a Morpheus. If you play on PC get a Rift. Looks simple to me.
About which one will be more successful, it's still doubtful. Sony has the advantage of owning both the device, the platform and games and could use their first party efforts to push it. Rift has to hope that 3rd parties will support a device that only a few have and that will demand a decent PC for gaming that very few have. Oculus has the advantage of trying new markets besides gaming and maybe hitting a casual hit in the long run.
I think it all depends on what focus will Facebook give to the Rift. Facebook is a tech company of course, but they aren't a hardware company (and failed pretty hard in their FB phone projects) and definitively isn't a gaming company. The hardware itself doesn't have any value if it doesn't have a (or several) killer app to sell it, like Wii Sports for the Wiimote and Kinect Sports/Adventure for the Kinect. In this aspect, Sony has the advantage of being capable of creating a killer game for their device. The wildcard here is that Facebook can have a non-gaming application that can move the Rift. But in this case, then the devices wouldn't even be competitors: a gaming virtual reality headset for PS4 vs. a non-gaming virtual reality headset for PCs.








