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jQuery2.0がリリースされたみたいっすよ。
http://blog.jquery.com/2013/04/18/jquery-2-0-released/

気になる旧式ブラウザへの対応については、

As promised, this version leaves behind the older Internet Explorer 6, 7, and 8 browsers. In return it is smaller, faster, and can be used in JavaScript environments where the code needed for old-IE compatibility often causes problems of its own. But don't worry, the jQuery team still supports the 1.x branch which does run on IE 6/7/8. You can (and should) continue to use jQuery 1.9 (and the upcoming 1.10) on web sites that need to accommodate older browsers.

とのこと。

IE8以下も考慮して、jQueryの読み込み方を変えてみるとか。

<!-[if lt IE 9]>
<script src="http://code.jquery.com/jquery-1.9.1.min.js"></script>
<![endif]->
<!-[if gte IE 9]><!->
<script src="http://code.jquery.com/jquery-2.0.0.min.js"></script>
<!-[endif]->

サイトの要件に応じて使い分けたいところです。