On one hand, championships are not everything. Hell, nobody is ever going to say Bill Russell was the greatest player who ever lived despite the absurd championship run back them. Not that he wasn't an amazing player, but times were different. Even between Jordan's prime and now, the NBA is different.
On the other hand, Jordan did what Lebron tried, and failed, to do. He took a mediocre at best team and turned it into one of the most dominant basketball teams in the history of the sport. Yes, it didn't happen immediately, it took time and building a supporting cast that included Scottie Pippen. Nevertheless, the turnaround is largely due to Jordan. And in the later years of his career Jordan became increasingly aware of the importance of team effort and became a batter passer and leader. Lebron was unable to do at Cleveland what Jordan did in Chicago, and it remains to be seen whether he can even come close to doing what Jordan did with a team as stacked with stars as Miami.
It's too early to reliably gauge Lebron's career overall. Nevertheless, you can't compare him to Jordan. Jordan single-handedly dominated the sport in an era that was stacked with legendary players (think of all the incredibly Hall of Famers/future Hall of Famers that never got a championship for no reason other than Jordan existing ... Ewing, et al.). Lebron is great, yes, but he doesn't dominate the league, and he hasn't changed the sport. Michael Jordan single-handedly changed the entire face of the league. Until Lebron does that, you cannot even begin to compare him to a player of Jordan's level. You can say he is more athletic, sure, and stronger, both of those hold water. But trying to compare them as overall players is pointless.