A while ago, the third million .nl domain name was registred at SIDN (.nl registry). So this extension is doing a very good job. According to SIDN, there could still be a lot more registrations under this extension. Surveys show that a lot of people, especially habitants of the Netherlands, are willing to register a .nl domain name but for some reason they don’t.
That’s why .nl registry starts with a large campaign to promote this extension. This campaign will contain leaflets, ads,… and will especially be visual in the Netherlands.