There might be a glitch or hack that might mess up the experience.... However I think its fair to trade with villagers since emeralds are supposedly harder to find that diamonds... And you need multiple in trade!

I like that there is a new ore/element, but the trading is a bit stange, since there will never be a way to make things perfectly fair. I think the trading should have only stuff with equal value. for example, a gravel block for a piece of flint. Or, stuff that requires the same amount of effort to get, such as blaze rods, you should have to do something about as difficult to be able to trade. On servers, I think using emeralds as the new currency makes it easier than getting a plugin and remembering all the commands, etc. The trading should also be able to bargain, like say a deal that would work in the snapshots, they might change it so the villagers say it's a stupid deal or a good deal. Also, it should sense if you stole their wheat, so you can't trade with the villagers own wheat. That way people can't get tons of stuff right away. Also, the villagers should attack all agressive mobs with pitch forks,torches, etc. (An angry mob to attack the monsters). Plus the villages should be able to punish you by putting you in jail if you kill a villager, or have some sort of punishment system for hurting/killing/stealing/using their houses, like a jail, and you would loose a few unimportant items from you inventory (Say a stack of dirt or something). One last question: Should I send these ideas to Mojang/Notch?