JavaScript: Detect Internet Explorer Version. Detects IE10, extended version of this http://stackoverflow.com/questions/4169160/javascript-ie-detection-why-not-use-simple-conditional-comments/4228216#4228216

detect_ie_version.js

// ----------------------------------------------------------
// A short snippet for detecting versions of IE in JavaScript
// without resorting to user-agent sniffing
// ----------------------------------------------------------
// If you're not in IE (or IE version is less than 5) then:
// ie === undefined
// If you're in IE (>=5) then you can determine which version:
// ie === 7; // IE7
// Thus, to detect IE:
// if (ie) {}
// And to detect the version:
// ie === 6 // IE6
// ie > 7 // IE8, IE9 ...
// ie < 9 // Anything less than IE9
// ----------------------------------------------------------
var ie = (function(){
    var undef,
        v = 3,
        div = document.createElement('div'),
        all = div.getElementsByTagName('i');

    while (
        div.innerHTML = '<!--[if gt IE ' + (++v) + ']><i></i><![endif]-->',
            all[0]
        );

    if (Function('/*@cc_on return document.documentMode===10@*/')()){
        v = 10;
    }

    return v > 4 ? v : undef;
}());