A good content management program will also help both your PageRank (PR), and website authority. When your authority goes up, so will your rankings. You can do this with a blog, but you need to add new, relevant content to your website. If you have specialized knowledge in your industry, you should be able to add content relevant to your industry and rank for the content. In additional to helping with your rankings, it will help you qualify your products and services with your web site visitors.