If you want to know why the relationship between blogs and search engines is important, here’s a good place to start. T. L. Pakii Pierce of How to Blog for Fun and Profit! has written "Search Engine Marketing for Beginning Bloggers."
The bottom line:
[…] Blogs are natural search engine optimization tools. The search engines love blogs and they crawl them frequently looking for great products (your content in search results) to take back and sell to their customers (that’s you and I when we do searches).
Blogs are crawled more frequently when they are updated frequently. This means that when you publish a steady stream of great content and you publish it often your content will get crawled often. This results in your content potentially being indexed much quicker as well as ranking much higher for relevancy and freshness.
Definitely worth time reading.
How to Blog for Fun and Profit! | Search Engine Marketing for Beginning Bloggers