Can a blog replace a promo site?

Recently, someone on one of my lists had a question. While he knew that it was important to have a website and he'd heard a lot about the SEO goodness and other associated benefits of having a blog, he wanted to know which was more important - the blog or the promo site? Could you just go with a blog instead of a more static promo site and still get the same results?

The answer is a bit complicated, but I'm a firm believer in having both - for a variety of reasons.

Blogs are great for SEO and getting recognition for your business (especially establishing you as an expert in your field, which is marketing gold). The challenge with using blogs instead of a more basic promo site is the fact that a blog, while it can give lots of great information about your field and things you do within it, doesn't accomplish the main goal of a company's website - to outline their offerings and show a potential customer why they should choose them over the competition.

While you can use a blog to provide information that enforces the points made on your company site (as I do with this blog and the zen kitchen's site), the promotional site, to which the customer can turn for basic information about the company, its mission, contact info, etc. is still an important piece of the puzzle that shouldn't be overlooked.

The goal of a promotional site is to make it extremely easy for the customer to get the information they need to know whether they want to work with your company - that means contact info, client case studies/testimonials, a breakdown of what you do and why you do it better than the competition is right there in front of the customer, and extremely easy to find (preferably in the top navigation, which is where the average user will look). Traditional blogs, with their emphasis on throwing all the most recent posts on the first page, make it harder for folks to answer the key question a user will ask when they visit your site: what is this company, and why should I work with them?

Given this, you can use most blog software to create a site that accomplishes both goals, and updating content regularly (for example, posting to the attached blog) will enhance the SEO of the site, as will being active on other blogs and social networks. So, unless you're looking for special advanced functionality (which would require custom programming and can drive costs up), a talented designer can create a site that maintains the structure of a promotional site while having the SEO benefits and (relatively) easy updating of a blog.