There is currently a glitch with the "promoted" page where it only shows the top 5-10 promoted posts. Any posts below those first few are not loading. This means if you promote your post for a small amount (anything less than what it takes to show up in the first few) then your post will not show up even though you promoted it. Please keep this in mind if you are planning to use the promoted page. It pretty much only works if you are in the top few.
I created a GitHub issue for this:
https://github.com/steemit/steemit.com/issues/586