<!DOCTYPE html>
<html>
<head>
<title>Test</title>
</head>
<body>
<div id="w"></div>
<script type="text/javascript">
alert( w );
w = null;
alert( w );
</script>
</body>
</html>
Try this test in IE8. You will figure out that w is global and cannot be overwritten.
Change "w = null" in "var w = null" and reload (after emptying cache)...
IE8 checks for variables before runtime and removes the global correspondent.
I really can't await the day when web developers don't have to support IE8 any more...
HINT: don't use variable names equal to DOM element id's.. OMG OMG
