Search result theming
Assuming Drupal 7 here, which thankfully has more options for you that Drupal 6.

I don't recall the last time I fully traced this out (and it's complicated), but search_excerpt does call strip_tags and check_plain.

You can take a look at search-result.tpl.php, template_preprocess_search_result(), hook_node_search_result() to see what your options are.

Personally, I would build up my own entries in $variables in the preprocess, and display them in the template.  One option is to make a custom node view for the search results, uild it up with the UI, and then use this,something like:

function mytheme_preprocess_search_result (&amp;$variables)
{
  $result = $variables['result'];
  $node = $result['node']; // not 100% positive that this is the right place in D7
  $variables['my_custom_search_result_view'] = node_view($node,
    'my_custom_search_result_view');
}


and then use $my_custom_search_result_view in search-result.tpl.php.

Not a full solution for you, but it should be a decent start.