Actually, you are quite right when it comes to header/footer. Here is some basic information on how each of the major HTML5 tags can/should be used (I suggest reading the full source linked at the bottom):
WYSIHTML5 – A better approach to rich text editing wysihtml5 is an open source rich text editor based on HTML5 technology and the progressive-enhancement approach. It uses a sophisticated security concept and aims to generate fully valid HTML5 markup by preventing unmaintainable tag soups and inline styles.
New Elements in HTML5 The internet has changed a lot since HTML 4.01 became a standard in 1999.
ABOUT THE TEST The HTML5 test score is an indication of how well your browser supports the upcoming HTML5 standard and related specifications. Even though the specification isn’t finalized yet, all major browser manufacturers are making sure their browser is ready for the future. Find out which parts of HTML5 are already supported by your …