Improvements over NotebookLM:
(1) You can start with just a subject, and you don't need a full document to begin (though you can do that too![1])
(2) The podcast generates much faster
(3) The podcasts are interactive -- you can ask the hosts to change direction mid podcast, and they will do so.
(4) (Coming soon) You'll be able to make a Spotify-style Queue of Podcast topics, which you can add to as you encounter new ideas.
The primary tradeoff is that the voices / personalities are somewhat less engaging than NotebookLM at this time, though this will be dramatically improved over the coming months.
This is all in addition to the core value proposition, which is roughly "AI Generated Duolingo for Any Subject".
It's early days, but I'd love for you all to check it out and give me feedback :)
[1] Documents are currently heavily length-limited but this will be improved shortly