It is that simple. You don't need to wait for people to start writing interesting stuff. You don't have to dig through forum posts searching for news people post whereever they feel like.

Just set some rules for participation and ask people to follow them.

Stop listening to those saying «Give people place to share thoughts, and they generate tons of content». I've been trying to do that for years. Forget about motivation. People are not traffic, they're individuals. Communicate. Ask.

http://en.miheev.info/2010/05/06/as-simple-as-that.html