Google's NotebookLM has received a significant update, reportedly powered by Gemini 3.5, which is said to be a major upgrade. The update is expected to improve research capabilities, with some outlets suggesting it increases the context window to fit a large number of tokens and provides more outputs. However, the exact details and features of the update are not entirely clear, with some outlets mentioning different versions of Gemini, such as Gemini 3.1 and Gemini 3.5.