I'm in the same boat as AnnMarie. I sort of dabbled when it first started, but haven't done much with it. I'm not sure how to promote as such, but it's probably worth looking into. I am far preferring the new myspace. I think it's what G+ was trying to be, but failed at it.
I dabbled with it when it first launched and left because it was DEAD. I have yet to venture back. I think it's something we should all be on one day but there seems to be a loss of interest all around right now.
We just started a Fourculture page on the new MySpace, which is a great platform for music and visuals. I'm liking it so far. It has yet to formally take off but a good number of people are on it. I can send you an invite for that if you'd like. It may be a nice resource for new music.