To me blogs are a strategic business communication tool. I usually consider the fact that blogs rank high in search engines to be a positive side effect. But I also recognize that for some people search engine optimization, SEO, is a major reason for blogging - and I have found it to be a good reason for others to start thinking about blogging at all. Here's a list of explanations to why your blog probably will rank high in search engines. And it's more to it than just the links.

The links are important, though. Especially to Google. Yahoo and the MSN Beta seems to give content related factors more weight in my experience. But even with Google the key to your success doesn't lie in links alone. If you want traffic through search engines you must get the basics right too.

So, here's my take on why blogs rank high in search engines.

    Keywords, key phrases
    Straight to the point
    Each post's page structure
    Coding
    One subject per post
    The blog site's information structure
    Links then...?

Keywords, key phrases
If I wanted to pick one single reason I would actually choose this one: In a blog you talk. You engage in conversations. You think out loud, in a way. The things you say are (hopefully) everything but the standard corporate bullxxxx. This means you are filling the engines' databases with relevant keywords - relevant because most of us search for the words or phrases we use daily. The same words you use in the blog because you talk instead of sending messages to the target audience.

Straight to the point
How many blog posts have you seen with this kind of headline: "Our software system solution for world-wide data quality"? How many corporate sites have you seen...? This point is related to the first one but it adds one extra dimension. Not only do we in blogs speak like real, living people in the words we use - we say it directly. Straight to the point. There are certainly exceptions to this, I admit that. But generally speaking I have found it to be true in many business blogs. To say what you want to say as fast as possible is important, which leads me to my next reason.

Each post's page structure
It's more or less standard in blog design to use the post's title/headline as the page's title (together with the blog name). With my two previous reasons in mind you now see how the html title is filled with tasty keywords. And that's the most important place to have them. That's where search engines expect to find the best clue to what your page is about, and they rank the words there high in comparison to other positions in the code. Speaking about code...

Coding
If you use blog templates they will probably be an example of good coding. Most I've seen has been at least. It's often a table-less design, an extensive use of style sheets, correct coding where headlines not only are larger and bold but actual H1's, H2's and so on. It's a clean code - good for browser compability, good for visitors with disabilities. Good for search engine spiders. Here you have a potential risk. If you just use the old CMS templates for your regular site, you may loose this advantage. The solution is of course to redesign all of it in line with this "modern" web design.

Finally, some reasons relating to information structure.

One subject per post
This is all about keyword density, which is the ratio of the word someone searches for against the total numbers of words on the web page. Most blog posts are rather short, and they're often about one subject. That means a good chance of a high keyword density - especially if you compare it to a standard corporate web site where you try to tell about all your products on one page, or very few pages.

The blog site's information structure
Blogs are "flat" sites. They have a first page (level 1), current posts (level 2), about page (level 2), archive pages (level 2) and archived posts (level 3). That's it. It's not clear exactly how important this is. Some claim spiders don't regularly index very deep sites and that low-level pages are given lower ranking, others say this is not a factor to care about.

Links then? Well, they will do you good too. A high Google PageRank is obviously better than a low. But if you don't get the above things right, the PageRank won't mean as much to you as it otherwise would have.