Google has made Gemini 3.5 Flash the default model behind AI Mode in Search worldwide, as part of its Search I/O 2026 announcement. The same update expanded agentic search, where AI Mode acts for the user by comparing options, booking or buying, and added generative UI to results. Personal Intelligence features now reach nearly 200 countries and 98 languages without a subscription. The Verge called it the biggest redesign of Search in years.
This article brings together our earlier reports on Gemini 3.5 Flash from June and September 2026.
What changed
- A faster default model. Gemini 3.5 Flash now answers in AI Mode everywhere. Google is optimising for speed and getting the task done.
- Search that acts. Agentic features let AI Mode complete tasks such as comparing, booking and purchasing inside Search itself.
- A wider audience. Personal Intelligence is available in nearly 200 countries and 98 languages with no paywall, so more ordinary searches end in a generated answer (Google's regional announcement).
Why it matters for being cited
More searches now end in an AI answer rather than a list of links. McKinsey estimates that about half of Google searches already show an AI summary, and expects more than 75% to by 2028. Sources named in AI Mode answers still get attribution, but a page is competing to be the source an answer, or an agent completing a task, relies on.
Google's own guidance on optimising for AI features has not changed: a page has to be indexed, crawlable and eligible to appear in AI features, and written for people rather than for shortcuts.
What to do
- Check you can be found. Any indexing or crawling problem keeps a page out of AI answers entirely.
- Answer specific questions directly. Pages that are factual, structured and cover the full intent behind a question (comparisons, steps and context) are the ones an answer can use.
- Measure where you stand now. Find out whether AI Mode and Gemini name your business for the questions your buyers ask, so you have a baseline to compare against as the rollout settles. Search Engine Land tracks how AI search products are changing across Google, Bing, ChatGPT and Perplexity.