To me it all boils down to competitiveness and mental approach to the game. Lebron has all the physical tools and skills in the world. I would even say he's a better all around player than Jordan every was. Lebron can play several positions very well and dominate.
But I watched the Cavs lose a game the other night. The game was over by the 3rd quarter. Lebron spent a good chunk of the 4th quarter on the bench, joking around, smiling, and have generally good time. Jordan would NEVER do that. He hated losing. He wouldn't let his teammates think that losing was acceptable. Jordan would never sit the 4th and check out mentally and celebrate a loss.
That's the difference between Jordan and some of today's players. They may be just as gift physically and skill wise, but they don't come close the mental aspect of the game and driving your team to victory each and every night.