Lego Batman doesn't bring anything particularly new to the franchise.
The gimmick of having a hero story line and a separate villain storyline is cool on the surface, and it almost makes it seem like you have twice as many levels to play as were in the previous games, but in practice it doesn't work out so well.
We're all used to playing story mode, then going back and playing the same level in free play, but this time, you have to go through the hero levels before you play the villain levels, and you have to play the villain levels before you unlock the villains to use in free play, and you have to have the villains unlocked before you can collect everything in free play mode, so you're almost done with the game before you start unlocking anything 'useful', like weapon upgrades. And even then, their usefulness is questionable.
For example, one of the unlocks is to make Robin's batarang when wearing the aqua suit freeze enemies. You can't throw the batarang while in the water, so the odds of my wanting to be in the aqua suit and use the batarang are already slim. You also can't throw the it if you get hit while you are targeting. So, if you really want to freeze someone, it's generally better to switch to Mr Freeze and use the freeze gun to do it.
The story is ok, some of the cutscenes are actually funny, the puzzles are about as complex as they could be in this type of game. The ai partner is not always real great at figuring out what you need them to do, leading to turning on my second controller to take direct control when I needed 2 levers pulled at once on more than one occasion, but this is also nothing new.
Worth a quick rent, but not something I would buy or feel the need to keep more than about a week and a half.
Batman is by far the best Lego game I have played to date. The gameplay is fun and the characters add to the great gameplay. The sounds is good and as expected. This, like any of the Lego games are renters in my opinion and well worth playing.