To me, "laid-back" has a very simplistic connotation, I look at it as "where" does the major component of the material seem to be coming from. Is the lead singer between me and the plane of the speakers? That's foreward. If I feel I'm on stage with the singer, that's foreward. If, like with my M3s, I find the singer is at the plane of my speakers, I think of that as neutral. If the speakers give me the impression that I'm in the back row of a theater or concert, that's laid-back.

That's my interpretation, anyway.
Rich.