Where Do You Get Traffic For Curated Content?

In episode 96 of our weekly Hump Day Hangouts, one participant asked about traffic sources for curated content.

The exact question was:

Hey guys, just bought Content Kingpin, checked it out already and I must say it is really another great product you guys produced and I am sure it can help me a lot with my business. Thank you for that.

What I would like to know is from where did you get the traffic to the curated content. Do you still have to promote the content by building backlinks, social signals and other stuff? Or do you get the traffic just naturally (from long-tail organic placement on Google)?