There will be a full review of Lego Batman in time; the short version will be that it's better than Lego Indy without being actually good. Some of its high points:
* You can play as the Joker, you can get his costume from the cover of The Killing Joke, and you can shoot Barbara Gordon in the spine.
* You can play as Bane and break Batman's back across your knee. (There is an Achievement for this.)
* You can punch Dick Grayson in the face until his head falls off.
That's a good start, but I was disappointed to find that Jason Todd is not present to recreate his fateful encounter with the Joker, and neither Black Mask nor Spoiler are available to continue the theme. I would also have liked, for comic effect, Thomas and Martha Wayne - when Martha Wayne breaks into her lego pieces she should spill little pearl-coloured studs.
I guess some dreams are not meant to be.