Gemini 3.5 Becomes the New Default Model
Google has rolled out a meaningful update to NotebookLM, its AI-driven research tool, making Gemini 3.5 the new default model. The update doesn't stop there — it also layers in Antigravity-powered software skills designed to help users tackle research tasks and generate a wider variety of outputs.
The direction is consistent with what Google has been doing across its products. Adding stronger AI capabilities to make tools more capable for complex Q&A is the same logic that drove coding enhancements to Google Search — making products more engaging and genuinely useful for the people who rely on them.
Building a Knowledge Base Directly From Chat
From Manual Sourcing to AI-Assisted Discovery
The biggest workflow shift in this update is how NotebookLM handles the early stages of research. Until now, users had to bring their own sources to the tool before it could start extracting insights or building out a knowledge base. That requirement is gone.
With the new update, you can open a chat, start talking about a project, and NotebookLM will begin suggesting relevant sources on its own — pulling from its built-in research skills and Google Search. That means the tool can find primary sources in other languages and surface material from related authors, broadening what's discoverable without making the user do all the legwork upfront.
Expanded Output Options and Detailed Instructions
More Control Over Format and Editing
Google has also given users more say over what NotebookLM produces and how. You can now give detailed instructions before generating output, and once it's generated, you can edit it directly. The range of supported export formats has expanded considerably:
- Data visualizations and charts (.png, .svg)
- Documents (PDFs, .docx, Markdown, text files)
- Nano-banana-powered images
- Structured data (.csv, .json)
- Microsoft Excel and PowerPoint
Having this variety built in means research outputs can move more directly into presentations, reports, or data workflows without needing extra conversion in between.
Transparent Reasoning Through Step-by-Step Thinking
Deep Research Mode Now Shows Its Work
NotebookLM introduced a Deep Research mode for structured online research last year. This update builds on that by making the reasoning process visible. The tool now surfaces detailed steps directly in the chat, showing users exactly how it arrived at its answers. That kind of transparency matters in research contexts — it gives users a way to check the output and understand what's behind it, rather than just accepting a result at face value.
Who Gets Access and When
The new features are available starting today for Google AI Ultra subscribers and all Workspace business customers with AI Ultra Access and AI Expanded Access. Google has said it plans to expand availability to additional users beyond these tiers.