We write our own unique content about our industry at large, not necessarily about our service. We have a website with a Pagerank of 6 and a blog as a sub-directory (ourdoamin.com/blog). Currently we post to our blog and have canonical links on the article pages. We have also been submitting to article sites using content crooner which in turn submits to ezinearticles, etc. We occasionally submit directly to these article sites to get the maximum allowance that may be limited through the auto submitters. The benefit is that on those sites, we can get 1-2 follow links to our main service pages.
In this scenario, are we penalized for having duplicate content or are only the article sites themselves penalized? If yes, how does it differ from sites like PRWeb that also syndicate content? Or are they also panda no-no's?