Section and header tags were standardized last year, it's definitely too early to tell how browsers will handle them, but with the ubiquity of CSS and for the reasons I already mentioned I doubt they will ever get any styling, unless maybe for when no CSS was defined at all.

Ultimately, I don't think of the web as a page-based medium, it's document-based. Electronic documents that want to mimic pages are a relic from the past, imo. What you seem to want should probably be implemented as browser plugins.