If it were any other game, we'd be complaining right now about the lack of real-time lighting and bump-mapped textures, but the Lego games are so charming it doesn't matter.
Lego Indy is the one everyone's talking about at the moment and will be hitting shops on June 6. Lego Batman is a little further off (no official date yet), but Travellers Tales looks to be working the same comical flair into the Batman universe, so it'll be worth the wait.
If you haven't already, you can see Internal Link
the latest trailers for the game here.