The real beauty of VR is the gameplay enhancement. In an RPG, you can look around as fast as you can in real life, and you can stop and hear the audio exactly where you are standing (it needs binaural audio!). The end result is true immersion. In a shooter, you can check behind you every now and then with a quick turn of the head, unlike the slow rotations of a DS interface. You can peak around a corner with just one eye. In a plane game you can look around in the midst of a dogfight. The experience will be fundamentally different, unlike every other variation such as 3D TV, which just adds a layer of depth and not immersion.
It's something I'd certainly like to try. It could be a game changer, which is why people are raving about Oculus Rift - it is an intrinsically different experience, putting you in the game as opposed to outside looking in through a window.
I think VR sells itself quite easily, and it's an experience that pretty much anyone would want to try. As you mentioned, immersion will be unparalleled. The only issue is making it easy to setup, convenient for a variety of spaces (wireless) and comfortable to wear for extended periods of time. From what I understand, people who have played long gaming sessions with the Occulus Rift say it is uncomfortable and dizzying after about an hour.