You will not be farming bosses. Bosses won't drop the best loot, they won't even drop really great loot. Part of Inferno and our intent with getting people out into the world and hunting and killing lots of different things is putting the best loot on rare and champion packs, and the great thing about rare and champion packs is they have random affixes. They're like a box of chocolates. Murderous, snarling, blood-soaked chocolates. You're not going up against a boss where you know "Build A" is the best way to minmax against it because it has abilities and resistances X, Y, and Z. What is the best build vs. an "Arcane Enchanted, Teleporter, Frozen, Knockback" skeleton pack? Got that figured out? Cause it's not going to be the best against the next pack you come across, and you're going to want to kill that one just as much.