That’s the ideal end product, but of course, Vodka is made from organic materials like most alcoholic things. From the Mythbusters episode on the related topic, it would seem that the main difference between ‘good’ and ‘bad’ vodka is how many times it’s distilled (run through a filter to remove everything but ethanol and water). Some alcoholic beverages are also concentrated by freezing the water portion to remove it. The stuff I buy, which seems to be the cheapest I can buy locally, claims to be ‘4 times distilled’. I guess that’s enough.
Makes sense to me.