I have never seen a site using MySpace OAuth login on the wild.. They certainly have no interest in it.
>My question is: What is their hook?
A good question. They kept their initial spirit: "Customizable homepages for Artists and Musicians." – But never overhauled the system to make it better, or useful than a Facebook fanpage. Only a redesign happened, when it was already too late. You obviously can't keep operating a `2000 Style` website 10 years later for the mass market. Myspace apparently has no hook.
Why can they do it better than some random bootstrapped people? They can't. They just have been there for longer than Facebook, which gives them a disadvantage, because people have a the original Myspace brand identity burned into their memory that will not go away, regardless how often Myspace re-writes the UI.