Google makes Gemini-powered AI Mode the default search across nearly 200 countries

Google made AI Mode, powered by Gemini 3.5 Flash, the global default across nearly 200 countries — what one analysis called its biggest search redesign in 25 years. More consequential than the interface, however, is Google's introduction of persistent AI information agents: background processes that monitor the web continuously, synthesize category intelligence, and deliver curated vendor shortlists to buyers without them ever returning to search.

For marketers, especially in B2B, the mechanics are stark. As Publicis Pro's Josh Cantwell-Crook describes it, a buying-committee member can describe a procurement need once, set an agent running, and receive recommendations with 'no landing page visit, no retargeting pixel, no attribution signal.' Gartner research cited in the piece notes buyers already spend just 17% of their purchase journey talking to suppliers; Google has now automated much of the rest using signals campaign managers cannot see.

Separately, studio A24 signed a generative AI deal with Google, and Gemini models continue to be evaluated for robustness in frontier health AI applications — signs of Google pushing Gemini into both creative and scientific domains.

Competitively, default AI Mode entrenches Gemini against OpenAI and Perplexity in consumer search while reshaping the entire SEO and performance-marketing economy. The new concrete facts are the ~200-country default rollout, the Gemini 3.5 Flash backing, and the persistent background-agent capability. The community warning is pointed: marketers fear buyer 'interception' may make traditional search traffic permanently obsolete. What to watch: how publishers and advertisers adapt, and whether regulators scrutinize Google steering shortlists through opaque agents.