It is becoming more common but the big question I get when talking to people is "Why use a blog?".

Off the top of my head I can think of 5 major reasons.

A blog is:

Easy to update

Easy to get started

Liked by the search engines

Creating feeds automatically

Allows people to interact with you

Before I start let me take just a minute to define the term blog. The following is quoted from Dr. Mani one of the earliest marketers to embrace blogs.

"A blog is short for "web log" a sort of online personal diary where "anyone" can reveal his/her innermost thoughts, feelings, desires, dreams, ambitions, fears, hopes - you get the meaning.

Yes, it's a website. With one small difference. It lists posts ordered by date in a personal journal format, and is easier to create than a website - just involves typing into a form and pushing the PUBLISH button"

The ease of push button publishing of most blog platforms make them one of the easiest web sites to update. On most platforms you don't need to know HTML though it does help. If you can create a word document you can update a blog.

They are extremely easy to get started. Blogger and Word Press both can be started without much more than creating an account and clicking a few choices. Now there are huge advantages to hosting your blog on your own domain. But even there if you have cpanel hosting with Fantastico it is an almost fill in the blank process to get started. No great technical skills needed.

Search engines like blogs. They are usually updated regularly because it is easy. Compare the type and push a button to update of the average blog platform to creating an HTML page uploading it either through the cpanel or FTP. Much easier so it happens much more often. Blogs tend to have fresher content.

The search engines also like the RSS feeds that are created. Properly used feeds can allow you to generate links from other authoritative sites such as Technorati, Feedburner and others. These high PR sites create backlinks to your site which will make the search engines rate you higher. People can easily subscribe to your feed and know when you have updated your site through various RSS readers.

Finally, the biggest advantage is that blogs can be interactive. Most blog platforms allow your reader to comment on what you have written.

This does two very good things for you. You get additional updated content (which the search engines like) and you get feedback on what you have written.