My idea is to grant users the ability to set-up "structured data" on blog posts to help with SEO.
Structured data is a system of pairing a name with a value that helps search engines categorize and index your content. Microdata is one form of structured data that works with HTML5. Schema.org is a project that provides a particular set of agreed-upon definitions for microdata tags.
Structured data seems to matter more often now with search engines and help boost SEO.