I've missed most of this discussion (might be a good thing), but I wanted to say that I listen to all of the musical submissions I have time for.

I rarely offer criticism or advice, but I do leave a (usually) inane little comment just to show the artist that I took the time to listen to his or her work, and that I appreciate him or her sharing it. Not leaving some sort of comment is like sitting in an audience and refusing to clap (even politely), imo.

Take care,
Dan