Move ShareThis link generation into a theme() function

I think it would be good to move the JavaScript for generating the ShareThis link into its own theme function. Something like this, I think:

function theme_sharethis_button($node_url, $node = NULL, $teaser = FALSE, $sharethis_sharethis_this_where = 0) {
  return "<script language='javascript' type='text/javascript'>
      SHARETHIS.addEntry({url: '{$node_url}', title: '{$node->title}'}, {button:true} );
    </script>";
}

That would allow a theme developer to create a custom theme function for the display of the button/link, and would also allow more control over what exactly is passed to ShareThis (e.g., additional supported properties like summary, published, etc.) as well as custom buttons using the technique described here: How do I create my own custom ShareThis button?.