By Evan Dawson, Managing Editor The other day I read a truly outstanding piece of wine writing by one of the most underrated writers in the field today. He's underrated probably because he's not actually in the wine writing field; Keith Levenberg is an enthusiast who makes his living elsewhere, but every six weeks or so, he rewards readers with his insights. His blog is not unlike your favorite greasy spoon tucked into high-end restaurant row: You always see the same dozen people there, and they realize that the place is going to be packed if anyone ever finds out how…