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Paste this code before </body>
</body>!? I've always been told to include JavaScript before </head>...
The problem caused by loading scripts is that they block parallel downloads. If the page is not parsed the user agent cannot know which subsequent resources need fetching, so a strictly conforming browser should not be able to fetch further resources until the first has actually been executed.
Since jQuery in particular shouldn't execute until the DOM hierarchy has been fully constructed, and HTTP/4.01 specification states "[a script] element may appear any number of times in the HEAD or BODY of an HTML document," it doesn't make sense to start those JavaScript downloads before the page's body has even started to download, and doing so would slow down the perceived page load.
It should therefore be included before </body>.