jQuery 2.0 does not support older versions of IE (IE6,7,8). What this means is that if you replace the current jQuery with 2.0 this will most likely break the compatibility of some controls with the mentioned browsers.
If you feel that support for older IE is not a must for your project you may try the 2.0 version, however, we cannot guarantee that it will work flawlessly with the RadControls.
What you can possibly do in order to avoid conflicts is to include jQuery 2.0 as a separate jQuery, which does not override the one provided by the RadControls.
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