Blueprint is already basically Haskell, I've done both and the similarities are striking. I think the world is ready for a proper visual programming language that plays nice with git, compiles down to native code and has all the nice abstractions that Haskell offers and none of the downsides of a scripting language. No doubt SPJ is one of the people who can help make that dream a reality, not in small part because just his presence will attract the best and brightest to Epic.
It doesn't have lambdas/closures. You have to create a whole separate object in a separate file to pass something new with data that can be called later.
Alright, it's maybe a bit hyperbole. If I'm thinking about what characterises Haskell, it's not that it has closures, it's that it makes control flow and side effects explicit through monads. Blueprint has a very similar idea where effectful/stateful code is ordered sequentially through the white lines, while pure functions are hooked up just through their inputs and outputs. It doesn't go much deeper than that, but looking at Haskell it seems blueprint really might go a lot deeper.