Although most themes for WordPress get this right, make sure your post title is an
<h1>, and nothing else. Your blog’s name should only be an
<h1>on your front page, and on single, post, and category pages, it should be no more than an
<h3>. Your sidebar shouldn’t be crammed with
<h3>‘s either etc.
These are easy to edit in the
page.phptemplates. To learn more about why proper headings are important read this article on Semantic HTML and SEO and our article about the Heading Structure for your Blog (from which a lot applies to non-blog WordPress sites too).
Realisation on snbchf.com
Our template strictly follow HTML guidelines for good on-page SEO, including the titles. We don’t use HTML5 structure, yet. But I think it is good idea to think for implementing it. It will give us positive Google ranking. Sites based on HTML5 are better indexed than sites on HTML4. We can still use our template and migrate to HTML5.