HTML5 allows us to embed metadata via the
data-* attribute. I would like to open a discussion on how we might be able to use the data attribute in Drupal core, or if we even should.
List of issues where the use of the data- attribute is relevant: (from comment #12)
#1217030: Clean up the CSS for Overlay module
#1216980: Clean up the CSS for Dashboard module
#1217032: Clean up the CSS for Poll module
#675446: Use jQuery UI Autocomplete