In the fast-moving world of generative AI, momentum is everything. While ChatGPT remains the giant of the industry by total volume, the last 30 days have signalled a definitive shift in power. Google’s release of Gemini 3 has not just closed the gap; in many critical metrics, it is starting to vault ahead.

Here is our analysis of how Gemini is taking over, and a side-by-side look at where the two titans currently stand.

The Surge: How Gemini Rocketed in Q4

For nearly three years, ChatGPT felt untouchable. However, the last month has rewritten the script. Following the launch of Gemini 3 in late November, Google has seen an explosion in consumer adoption that OpenAI is struggling to match.

The numbers are startling. In just the last quarter, Gemini’s user base reportedly leapt from 450 million to 650 million Monthly Active Users (MAU). This surge in traffic is fuelled by Google’s "full stack" advantage—leveraging its own custom silicon and deeply embedding Gemini into Android and Workspace.

Meanwhile, reports suggest OpenAI has shelved plans for new advertising features to focus entirely on fixing performance issues—a clear sign they are feeling the heat.

Head-to-Head: The New Reality

To understand the scale of this takeover, we need to look beyond just the total user count and examine how people are using these tools right now. The latest data reveals that users are increasingly choosing Gemini for deeper, more complex tasks.

Here is the state of play for December 2025:

Why the Shift is Happening

The data above tells us what is happening, but for marketers and strategists, the why is more important.

1. Superior Reasoning Capabilities

The consensus on the new Gemini 3 model is that it has finally cracked the "reasoning" barrier. Users are finding it more reliable for complex logic puzzles, coding, and academic work. The higher "Time Per Visit" for Gemini suggests users are staying to do real work, whereas ChatGPT is often still used for quick, transactional queries.

2. The Best Ecosystem by far

Google has stopped treating Gemini as a destination and started treating it as a utility. It is in your Maps, your Docs, and your search bar. This frictionless access is driving the kind of casual, daily habit-forming usage that a standalone app like ChatGPT struggles to replicate at the same scale.

3. Viral Wins

Google has also rediscovered its fun side. The new "Nano Banana" image editing feature became a viral sensation in November, driving millions of younger users to download the app who might otherwise have stuck with TikTok or Instagram for visual creativity.

The Verdict

The narrative of "ChatGPT vs The Rest" is over. We have entered the era of Gemini’s ascent.

While OpenAI still has a massive installed base of over 800 million weekly users, the energy and innovation are currently coming from Mountain View. For digital professionals, this means optimising for Google’s ecosystem is no longer optional—it is the primary battleground for 2026.

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