if url not equal to specified url then apply this jquery?
if the current url is not same as specified then apply jquery.

    <script type="text/javascript">
    var myurl = http://site.blogspot.com/2011/10/document.html;
    var currenturl = window.location
    if(myurl == currenturl) {
    $("<span>url's match</span>").replaceAll("body"); // check replaceWith() examples
    }
    </script>
also current url can be a standard link http://site.blogspot.com/ or as shown in example.
if url not equal to specified url then apply this jquery?
===

if the current url is not same as specified then apply jquery.

    <script type="text/javascript">
    var myurl = http://site.blogspot.com/2011/10/document.html;
    var currenturl = window.location
    if(myurl == currenturl) {
    $("<span>url's match</span>").replaceAll("body"); // check replaceWith() examples
    }
    </script>
also current url can be a standard link http://site.blogspot.com/ or as shown in example.