George R.R. Martin, in his Rolling Stone profile, sums up why A Song of Ice and Fire is better then Lord of the Rings:
Ruling is hard. This was maybe my answer to Tolkien, whom, as much as I admire him, I do quibble with. Lord of the Rings had a very medieval philosophy: that if the king was a good man, the land would prosper. We look at real history and it's not that simple. Tolkien can say that Aragorn became king and reigned for a hundred years, and he was wise and good. But Tolkien doesn't ask the question: What was Aragorn's tax policy? Did he maintain a standing army? What did he do in times of flood and famine? And what about all these orcs? By the end of the war, Sauron is gone but all of the orcs aren't gone -- they're in the mountains. Did Aragorn pursue a policy of systematic genocide and kill them? Even the little baby orcs, in their little orc cradles?
Martin makes my arguement for me. Speculitive fiction only works when the economics of the world makes internal scene.