MySpace was a social media platform like Facebook. Was very popular untill Facebook took over its user base and traffic.
Benefits? It gives a nofollow profile backlink but I doubt even that is of any benefit anymore.
I think you can get a link in your bio, IF you manage to open an account. I had difficulty last time I tried I think, so I just left them, and moved on to another web 2.0
MySpace has become more focused on music. So one can say if you are into music niche, then it may help .... But not sure about its statistics. When I was on MySpace, it was a happening place, but couldn't stand to the Social Network Wave ....