Creating blogs that speak about your services and getting your users to make testimonials and blog entries can certainly add value to your website, and links to product specific pages from these blogs would certainly drive traffic into those web pages.
Always ensure your keywords are used within the blogs that are made. That way while giving out the general message to a crowd you still manage to satisfy the search spiders with adequate keywords to drive traffic to these blogs. You can start an area in your website specifically for your users, to write reviews about your services and also to give out testimonials. This will generate new content without much of your time investment into it. Your customers can themselves be your marketers and help add pages and content to your website.
Search engines spider these websites more frequently than sites that do not use blogs, getting them indexed almost instantly. When managed properly, blogs can be an invaluable tool for your SEO, helping you to drive more natural incoming traffic to your web pages.