I have a web service that help bloggers to do certain tasks and find different partners. We have a couple of thousand bloggers using the service and ofcourse this is a great resource for us to build links from. The bloggers are all from different platforms and domains.
Currently when a blogger login to the service we tell the blogger that if they write a blog post about us with their own words, and tell their readers what they think of our service. We will then give them a certain benifit within the service.
This is clearly encouraging a dofollow-link from the bloggers, and therefore it's not natural link building. The strategy is however working quite good with about 150 new blog posts about our service per month, which both gives us a lot of new visitors and users, but also give us link power to increase our rankings within the SERP.
Now to my questions: This is not a natural way of building links, but what is your opinion of this? Is this total black hat and should we be scared of a severe punishment from Google? We are not leaving any footprints more than we are asking the users for a link, and all blogposts are created with their own unique words and honest opinions.
Since this viral marketing method is working great, we have no plans of changing our strategy. But what should we avoid and what steps should we take to ensure that we won't get in any trouble in the future for encouraging our users to linking back to us in this manner?