This is much better than smalltalk. In Smalltalk, you could just edit code on the fly, but nothing would happen if that code wasn't continuously executing in an infinite loop. LightTable, on the other hand, supports real liveness. Its something that we never got in Smalltalk or Lisp.
Edit: Morphic (from Self) does support liveness, but only when it is being edited at the graphical level. If you are editing code, you are stuck in the same refresh trap as Smalltalk or Lisp, but to be fair, morphs are continuously updating themselves in infinite loops so it doesn't matter :)
I'm sad that this comment is the last on this page and not the first. I imagine that - after LT is complete - some Smalltalkers will hold a competition to replicate it in 48 hours. I believe they would succeed - building on top of Smalltalk environment with Morphic[1] this shouldn't be too hard.
For those who don't know why: go grab Pharo[2] Smalltalk and "Pharo By Example"[3] book and play with it. It's absolutely beautiful, an experience well worth a few days of time.
I've a strong feeling that it's not a language matter anymore. People behind Smalltalk and Self are still active. Idioms are spread everywhere and such ideas will re-emerge.
