Think about it, when we have a bruise we use ice to dull the pain so we don't feel anything. That's how our tongue reacts to the Rockies ultra-cold glass and possibly the beer inside it, numbing your tongue to submission. In fact there have been studies on the affects of temperature on the tongue and taste or perceived taste; Effects of Solution Temperature on Taste Intensity in Humans, Effects of Temperature on the Perceived Sweetness of Sucrose, 'Thermal Taste' Predicts Higher Responsiveness to Chemical Taste and Flavor and Somatosensory factors in taste perception: Effects of active tasting and solution temperature.
Very Cold (0-4C / 32-39F): Any beer you don’t actually want to taste. Pale Lager, Malt Liquor, Canadian-style Golden Ale and Cream Ale, Low Alcohol, Canadian, American or Scandinavian-style Cider.
Cold (4-7C / 39-45F): Hefeweizen, Kristalweizen, Kölsch, Premium Lager, Pilsner, Classic German Pilsner, Fruit Beer, brewpub-style Golden Ale, European Strong Lager, Berliner Weisse, Belgian White, American Dark Lager, sweetened Fruit Lambics and Gueuzes, Duvel-types
Cool (8-12C / 45-54F): American Pale Ale, Amber Ale, California Common, Dunkelweizen, Sweet Stout, Stout, Dry Stout, Porter, English-style Golden Ale, unsweetened Fruit Lambics and Gueuzes, Faro, Belgian Ale, Bohemian Pilsner, Dunkel, Dortmunder/Helles, Vienna, Schwarzbier, Smoked, Altbier, Tripel, Irish Ale, French or Spanish-style Cider
Cellar (12-14C / 54-57F): Bitter, Premium Bitter, Brown Ale, India Pale Ale, English Pale Ale, English Strong Ale, Old Ale, Saison, Unblended Lambic, Flemish Sour Ale, Bière de Garde, Baltic Porter, Abbey Dubbel, Belgian Strong Ale, Weizen Bock, Bock, Foreign Stout, Zwickel/Keller/Landbier, Scottish Ale, Scotch Ale, American Strong Ale, Mild, English-style Cider
Warm (14-16C / 57-61F): Barley Wine, Abt/Quadrupel, Imperial Stout, Imperial/Double IPA, Doppelbock, Eisbock, Mead
Hot (70C/158F): Quelque Chose, Liefmans Glühkriek, dark, spiced winter ales like Daleside Morocco Ale.
Oh and don't forget your nose! Obviously we all know that the nose helps us to taste. Harken back to eating <insert nasty food you were forced to eat as a kid> and your mom said "just pinch your nose and eat it". It's almost accomplishing the same thing by drinking a very cold beer. Specific volatile components of aroma are released either not at all or very little in extreme cold. Which means that you won't get the full impact of what you're drinking.
Remember, though, that these are just guides as to what temperature you could drink a style of beer. If you more thoroughly enjoy an IPA at 32f, by all means do so. And if you want to drink a lawnmower beer because it's extremely cold and refreshing on a hot summers day, go right ahead, I'll be there with you! Just remember you may not get the same flavor profile that the brewer intended it to be. Although that American adjunct lager in a frosty mug is just what the brewer intended.
Chris @TheBarleyMen