Myth #1: Vodka is made from potatoes.
About one percent of all vodka brands is made from potatoes. Two of those brands are the American-made Blue Ice and the Polish luxury brand Chopin. A few vodkas such as Ciroc are made from grapes. Almost all the rest are distilled from grains, including wheat, rye and (especially) corn.
Myth #2: More distillations = better vodka.
There are two basic types of stills: pot and column stills. Nearly all vodka is column-distilled, as this produces the cleanest (most flavorless) spirit. When people refer to how many times they've distilled a vodka, it usually doesn't mean that they've run it through one column (or pot) still a bunch of times. Rather, they mean that that one still has a bunch of columns. But since it sounds so good to brag about the number of times the product is distilled, everybody does it.
Myth #3: Distillation has the greatest effect on flavor.
Distillation has a big effect, to be sure, but there is a whole lot more to vodka. After distilling, the vodka is filtered and diluted with water (that is also filtered) to reach the desired proof (alcohol content). Most vodka is 60 percent water, so the water in the recipe plays a pretty big role in the flavor. Brands who can do so tend to brag about using glacial spring water (Finlandia) or filtration through lava rock (Reyka).
Myth #4: There are thousands of vodka distilleries, one for each brand.
In the American Midwest, a few huge distilleries crank out generic vodka all day long. This vodka is then either bottled onsite or shipped for processing (dilution, filtering, flavoring, then bottling) somewhere else. A lot of what makes one vodka different from another happens at the individual processing facilities, not at the distillery -- and there aren't all that many processing facilities, either.
Myth #5: There are oranges in your orange-flavored vodka.
The difference between natural and artificial flavors is a technical rather than intuitive one, and your average lemon vodka never had a lemon floating in it. A few brands (Hangar One, Belvedere) actually do infuse fruit into booze, then mix it with vodka to flavor it, but most just add pre-purchased flavoring components to the tank of vodka.
Myth #6: Knowing how vodka is made makes it taste different.
So now that we know how vodka is (and isn't) produced, our brains are smarter -- but our tongues are just as dumb. When professionals do blind taste tests, they're oblivious to all the marketing messages as well as to how the specific brands they're evaluating were made. They, like you, can really only rely on the mouth. If you like how a vodka tastes (and how the bottle or supermodel looks), then go ahead and enjoy it. Just do so responsibly, and now a little more smartly