The content of Lego Indiana Jones 2 is somewhat odd. Not only does it feature Traveller's Tales' interpretation of the recent abomination of a film, but also apparently the first three films again, but with no repeated content. But most interesting at this point is the level creator that's coming with it, detailed in the developer walkthrough posted below.
Of course, we shouldn't be dismissing the Lego version of Indy 4. The Lego Star Wars games were much better when mocking the more recent trilogy than they were when reverentially paying homage to the original. Perhaps it's too soon, but I'm certainly hopeful there will be tongues in cheeks for this one. It's also interesting to wonder what they might be using of the original three films, and why they didn't choose to use them the first time. But anyhow, check the video for many more details, especially how damned cute the level builder looks: