Ask HN:how promote desktop Facebook music app get feedback to improve the idea?

first im sorry for the cross posting here and in Reddit,it was very imported for me to get feedback form both so here it is:

I had idea so I build prototype for desktop music app , something that will keep you updated with music. its divided to 2 main sections

* first is real-time music aggregation

* second part is small local db that holds the data

So you can keep the music links. its prototype but working one , I use it all the time also 2 of my friends .

my question is how can I promote it make it more viral get more suggestion on improving ?

( except posting link here).

thanks and here is the link use it on own risk ,its early alpha prototype .

http://code.google.com/p/play-list-builder/

Thanks!