yeah, you're right, sorry for being emphatic in my opinion. I hope that people read your post as inspiration to keep people from being a condescending ass.
L4D is a great example of something that is just not as good single player. Period. It's a social game and playing it with a headset is amazing if you have a good crew.
The difference is presence. They mean that your brain accepts the visual scenario as "real".
This thing where the PS4 isn't powerful enough is flawed logic.
The PS4 won't be able to push it's current games into that resolution, but if you can simply focus on performance (60-120 fps) and gameplay. There are a number of 3D games that, while dated, still have a solid art style going for them with unique enough gameplay experiences that people still play or will play at a discount price. Point is, lower the demand of polys and textures and you have plenty of horsepower for keeping the latency down and frames up.
Maybe you're old, maybe you're just not keeping up on what technologies and programming can do with this thing. OculusVR isn't just TRICKING everyone. The applications are many and there are even more unexplored ones.
Remote Telecommunications (http://youtu.be/yUu1ZQDCGp8)
Out of Body Experience Generator
Arcade Laser Tag
Point is it's not going to be a niche, it's going to be a lot of niches.