select.get('value');

Element.js

/*<ltIE9>*/
var testForm = document.createElement('form');
testForm.innerHTML = '<select><option>s</option></select>';

if (testForm.firstChild.value != 's'){
	Element.Properties.value = {
		get: function(){
			if (this.get('tag') == 'select'){
				var selected = this.getSelected()[0];
				if (!selected) return '';
				var attr = selected.getAttributeNode('value');
				return (attr.specified || attr.nodeValue) ? selected.value : selected.get('text');
			} else {
				return this.getProperty('value');
			}
		}
	};
}
/*</ltIE9>*/