Heres what they have to say about it:

"Spend your Steem Dollars to advertise this post in the promoted content section. This doesn't pay the author directly, instead the funds are "burned". When funds are burned, they become a dividend to shareholders"

They mention that the funds will be “burned”, now I’m not exactly sure what this means. What about when people up vote your post? Will those funds also be given to the shareholders? This is something that is extremely important to know when promoting a post. Are you doing this to gain up votes in order to make more money or are you just trying to spread the word about something. This is very important to have figured out when you go to promote your post.