Many people don't understand the point of blogging and can't see the great things it can do for our businesses. As an author it's a great idea to blog, especially if you have it attached to your upcoming book and webpage.
So what does it do? If you update your blog regularly it's going to increase your hit rate on search engines such as Google, Bing and Yahoo. In short it means that people can find you easily when they search for you. The more you post, the higher you will climb the ladder and drive traffic to your book.
Just make sure that you have a theme on your blog and keep posting good content!