The thing that puts Lebron ahead of everyone else is his defense. Durant, Chris Paul, Kobe and Tony Parker all deserved some consideration this year (Rose would have minus the injuries), but Lebron's defensive prowess and versatility put him ahead of all of those guys. Kobe can still defend in spurts, but Lebron can shut down almost all five positions throughout a 48 minute game.
Take the Knicks series. Lebron spent time on 'Melo, Chandler, Amare and JR Smith. There's not another guy in the league that can check that range of guys. Battier was on 'Melo most of the time, but when Lebron had him, 'Melo wasn't nearly as effective of a scorer.
I completely understand the hate directed at Lebron, but the guy is unquestionably the best, most talented, most valuable, etc, player in the league and it's not even close. Sure Durant and 'Melo are probably better pure scorers, and Kobe is probably still the most feared closer in the game, but there's not another guy in basketball that can produce and impact a game like Lebron.
And to counter that whole, "the Heat would still be good even without Lebron" argument, look at their record without Lebron compared to their record without Wade, and then look at the disparity in the +/- when Lebron is on and off the floor. The Heat are a .500 team without him and almost an .800 team with him.