I disagree with language like 'reimagining programming' in this context almost as much as I regret seeing Bret Victor's name being dragged in for no reason -- to the best of my knowledge, Bret Victor didn't design Light Table, and doesn't inform its progress.
There is progress to be made, and I'll be excited again when I see some.
I've seen the same "oh, this is only for beginners" reaction to some of Victor's ideas on making data visible and making libraries "discoverable" that seems needlessly dismissive. That's why I mentioned him. Also, Light Table's initial concept was inspired by his work[0].
I'm not always impressed by Light Table, but I appreciate the work the team has put into the problem and think they have good ideas.
The problem with a program-as-the-mental-model is that you will invariably hit a barrier (whether that be the halting problem or some simpler manifestation). I'm much more sympathetic to the Don't Kill Math[0] view. You need (abstract) analysis and no amount of IDE bling is going to eliminate that necessity.
There is progress to be made, and I'll be excited again when I see some.