Dwayne Allen of Rum Bar Gives a Tasty Tutorial on Rum
Dark -- Rich, full-bodied, caramel-dominated rums. These are sipping rums, offering up flavors of chocolate, coffee, tobacco and nuts. Think Zaya 12 year, Appleton Estate 12, Zacapa 15 or 23 Year.
Black -- Even darker, richer and more syrupy with a strong molasses flavor. This rum is used for baking and making candy. It's also a natural with lime and ginger beer (ever tried a Dark & Stormy?) Think Gosling's Black Seal or Cruzan Black Strap.
Spiced -- These may be white, golden or dark rums, infused with natural (or not-so-natural) spices, caramel or artificial fruit flavors. They tend to be sweeter. Allen isn't much on these, but if you must, think Cruzan 9 Spice or Sailor Jerry.
Overproof -- Use for floats on tropical cocktails (they flame because of the high alcohol content), overproof rums are usually 60% (or more) alcohol by volume, which is to say, 120 (or more) proof. Try Wray & Nephew. Better than Bacardi 151.
And here are a few rums I sampled: