For Veit. Here's how to change itemprop for site title or entry title in Genesis. These go in your functions.php of your child theme.

Changing title attributes

add_filter( 'genesis_attr_site-title', 'dc_veit_site_title' );
function dc_veit_site_title( $attributes ) {
	$attributes['itemprop'] = 'nonheadline';
	return $attributes;
}

add_filter( 'genesis_attr_entry-title', 'dc_veit_entry_title' );
function dc_veit_entry_title( $attributes ) {
	$attributes['itemprop'] = 'whatever';
	return $attributes;
}

Thanks for posting this!