a simple jquery plugin that wraps styled tags with specified tags

jquery-just-html.js

(function ($){
    $.fn.wrapInHtml = function (options) {
        var tags = $.extend({i: {css: 'font-style',
                                 val: 'italic'},
                             b: {css: 'font-weight',
                                 val: 'bold'},
                             u: {css: 'text-decoration',
                                 val: 'underline'}},
                            options);

        return this.each(function () {
            var $node = $(this);

            $.each(tags, function (tag, prop) {
                if (prop === undefined) { return; }

                if (prop.val === $node.css(prop.css)) {
                    $node.css(prop.css, '');
                    if ($node.is(tag)) { return; }
                    $node.wrap('<' + tag + '>');
                }
            });

            $node.children().wrapInHtml(tags);
        });
    };

    $.justHtml = function (str, options) {
        var $root = $('<p>').html(str);
        return $root.wrapInHtml(options).html();
    };
})(jQuery);

// usage
var $input = $('some-selector'),
    $output = $('another-selector'),
    justHtml = $.justHtml($input.html(), {i: null,
                                          em: {css: 'font-style',
                                               val: 'italic'}});

$output.html(justHtml);