Using jQuery 2.0.0 with a fallback to 1.9.1 for IE8 & below. Used on this blog post: http://nukoagency.co.uk/2013/05/dealing-with-old-browsers/
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<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.0.0/jquery.min.js"></script>
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<!--[if lte IE 8]>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js"></script>
<![endif]-->
<!--[if gt IE 8]>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.0.0/jquery.min.js"></script>
<![endif]-->