In working on the seo for bloggers book and dealing with blogging clients, I’ve come up with a handful of things you (or your blog software) should definitely do if you want to rank well in the search engines.
These are the absolute necessities of blog optimzation.

1. Automatically send and receive trackbacks
2. Automatically ping blog services when new post is made
3. Maintain a blogroll
4. Single-post page title tags contain the post’s title
5. Permalink URLs contain the post title
6. The post title is the link to the permalink page
7. Post titles are wrapped in heading tags
8. Create multiple paths for spiders through your archives (monthly, related posts, most popular, etc)
9. Use categories and make them keyword-rich