NotebookLM expanding upload sources to include YouTube videos alongside PDFs and Google Docs changes what knowledge goes into a notebook

YouTube videos being uploadable as sources alongside PDFs, Google Docs and web pages changes the knowledge sources that can populate a notebook. Research that lives in YouTube talks, conference presentations, tutorial series and expert interviews can now be incorporated into a NotebookLM notebook alongside text sources. A notebook on a technical topic that includes the relevant YouTube lectures, key papers and reference documentation is a more complete knowledge resource than one limited to text sources.

The expanded capacity for both free and Plus versions being increased alongside the new source types changes the practical scope of what a single notebook can contain. The limit on notebook size has been a real constraint for comprehensive research on broad topics.

The Audio Overview converting notebook content into an AI-generated conversational discussion between two AI hosts is the audio format that changes when and how you can engage with research content. The podcast-style format being genuinely conversational rather than just narrated text changes the listening experience enough to make it useful as a review mode rather than just an alternative reading format.

What is the most useful YouTube source type you would want to incorporate into a NotebookLM notebook and how would having it searchable alongside text sources change your research workflow?