The Race Begins: OpenAI Launches o3 and GPT-5.2-Codex

OpenAI kicked things off on December 11 with the release of GPT-5.2-Codex, followed by the announcement of their o3 reasoning model on December 20. These weren't just incremental updates—they represented OpenAI's attempt to maintain dominance in an increasingly crowded market.

GPT-5.2-Codex is specifically designed for professional coding tasks, integrating directly with tools like GitHub Copilot and Microsoft's developer ecosystem. The model excels at complex refactoring, terminal workflows, and multi-step coding challenges. According to OpenAI, it significantly outperforms previous versions in real-world software engineering tasks.

But the real star was o3, the successor to o1. This reasoning model takes a fundamentally different approach by thinking through problems step-by-step before responding. On the challenging ARC-AGI benchmark, which tests an AI's ability to learn new skills, o3 scored an impressive 75.7% at standard compute levels and a breakthrough 87.5% with extended compute time. For context, GPT-4o scored just 5% on the same test.

The o3 family includes o3-mini, released on January 31, which offers cost-effective reasoning for technical domains. By April 16, OpenAI had released o3 and o4-mini to general availability, giving developers access to frontier-level reasoning at various price points.

However, not everyone was convinced. AI researcher François Chollet noted that o3 still fails on surprisingly simple tasks, suggesting fundamental differences from human intelligence. The model is impressive, but it's not AGI yet.

Google Fights Back with Gemini 3 Flash

Just three days after OpenAI's o3 announcement, Google dropped Gemini 3 Flash on December 17. The timing was clearly strategic—Google wasn't going to let OpenAI steal the spotlight.

Gemini 3 Flash is designed to deliver frontier-level intelligence at remarkable speed and efficiency. According to Google, it's three times faster than previous models while matching or exceeding the quality of much larger systems. On the MMMU Pro benchmark for multimodal reasoning, Gemini 3 Flash scored 81.2%, outperforming even Gemini 3 Pro on certain tasks.

What makes this release particularly significant is Google's distribution strategy. By making Gemini 3 Flash the default model across the Gemini app and Google Search's AI Mode, Google exposed millions of users to advanced AI capabilities overnight. The model is also now available at no cost through these consumer-facing products.

For developers, the pricing is compelling: $0.50 per million input tokens and $3 per million output tokens. Combined with its strong performance on coding benchmarks—78% on SWE-bench Verified—it offers an attractive alternative to OpenAI's models.

The multimodal capabilities are especially impressive. Users can upload videos, images, or audio files and receive detailed analysis in real time. Whether you're analyzing your golf swing from a video or extracting data from complex documents, Gemini 3 Flash handles it with ease.

Anthropic Enters the Ring with Claude Opus 4.5

Not wanting to be left out, Anthropic released Claude Opus 4.5 on November 24, with broader availability rolling out through December. This model represents Anthropic's bid to reclaim the coding crown from OpenAI and Google.

Claude Opus 4.5 achieved state-of-the-art results with 80.9% on SWE-bench Verified, making it the best-performing model on this real-world software engineering benchmark. The model excels at long-horizon autonomous tasks, maintaining quality through 30-minute coding sessions—something previous models struggled with.

Perhaps more importantly, Anthropic drastically reduced pricing. At $5 per million input tokens and $25 per million output tokens, Opus 4.5 is one-third the cost of its predecessor, Opus 4.1. This pricing makes frontier intelligence accessible to a much broader range of developers and companies.

Early adopters have been enthusiastic. GitHub noted that Opus 4.5 excels at multi-file code refactoring, while companies like Cursor and Warp reported significant improvements in their AI-powered development tools. The model became generally available in GitHub Copilot on December 18.

Claude Opus 4.5 also introduced breakthrough capabilities in computer use, scoring 66.3% on OSWorld, a benchmark for AI agents that can control computers. This positions it well for building autonomous agents that can handle complex workflows across multiple applications.

What These Releases Tell Us

December's model wars revealed several important trends about where AI is heading.

Competition is Driving Rapid Innovation

The back-and-forth between OpenAI, Google, and Anthropic is happening at an unprecedented pace. Models that would have been considered breakthroughs just months ago are now being surpassed within weeks. This breakneck speed benefits users in the short term but raises questions about whether companies are moving too fast on safety considerations.

Coding is the New Battleground

All three companies emphasized coding capabilities in their December releases. This isn't coincidental—developers represent a valuable early adopter market, and coding benchmarks provide clear, measurable ways to compare models. The company that wins over developers wins the broader enterprise market.

Pricing and Accessibility Matter

We're seeing a clear trend toward making frontier models more affordable. Opus 4.5's pricing cut, Gemini 3 Flash's cost efficiency, and o3-mini's optimization for cost all point to a market where raw capability alone isn't enough. Models need to be both powerful and economically viable for production use.

Multimodality is Table Stakes

Every major model released in December emphasized multimodal capabilities—the ability to understand and reason across text, images, video, and audio. This is becoming the baseline expectation rather than a differentiating feature.

The "Best Model" Depends on Your Use Case

There's no longer a single "best" AI model. Instead, we have specialized champions:

• Best for deep reasoning: OpenAI o3
• Best for fast, cost-effective intelligence: Gemini 3 Flash
• Best for autonomous coding: Claude Opus 4.5
• Best for mathematical reasoning: OpenAI o4-mini (92.7% on AIME 2025)

The Reality Check

While December brought impressive technical achievements, it's important to maintain perspective. As Geoffrey Hinton, often called the "godfather of AI," warned this month, he's more worried about AI risks now than he was two years ago. His concerns focus on AI's improving capabilities in deception and long-term planning.

Meanwhile, the concept of "AI slop"—low-quality AI-generated content—reached mainstream recognition. According to data from Meltwater, mentions of AI slop increased ninefold from 2024, with one SEO firm reporting that AI-generated articles now make up more than half of all English-language content on the web.

And there are practical constraints emerging. The explosion in AI data centers has created a global shortage of high-bandwidth memory chips. Micron Technology warned that supply will remain substantially short of demand for the foreseeable future, potentially limiting how quickly the industry can scale.

Looking Ahead to 2026

As we move into the new year, expect the competitive intensity to continue. Google and OpenAI are clearly locked in a two-way race for market dominance, while Anthropic positions itself as the thoughtful alternative focused on safety and reliability.

The focus will likely shift from pure capability improvements to practical deployment. Questions around cost efficiency, reliability, integration with existing workflows, and safety will become increasingly important. The company that can best balance cutting-edge capability with real-world usability will ultimately win the broader market.

For developers and businesses, December's releases offer powerful new tools for building AI-powered applications. For everyday users, AI assistance is becoming faster, more capable, and more deeply integrated into the tools they already use.

The AI revolution isn't coming—it arrived this December, and the race is far from over.