ChatGPT's dominance in the generative AI market is shrinking, with its global traffic share dropping from 66.8% in December 2025 to 64.6% by mid-January 2026. Google's Gemini is gaining ground, increasing its share from 19.5% to 22% in the same period. A year ago, ChatGPT held an overwhelming 86.6% of the market, but it has shed over 22 percentage points in just one year, highlighting intensified competition. Other players are also showing movement. xAI's Grok has overtaken DeepSeek for the first time, capturing 3.5% of traffic compared to DeepSeek's 3.3%. Meanwhile, Claude remained stable at 2.1%, and Perplexity dipped slightly to 1.9%. Microsoft's Copilot continues to decline, now at 1.1%. Data from the week following the holidays indicates a rebound in AI tool usage, with the General AI category growing by 2% after a significant post-holiday decline. Gemini's traffic boost is partly due to its integration into Google's ecosystem, with the user base climbing from 450 million in July to 650 million by October 2025. This growth coincided with the release of the Nano Banana image generator and a new partnership with Apple that positions Gemini as the backbone for Apple's forthcoming AI initiatives. In contrast, ChatGPT drove over 1.6 billion visits to external websites between September and November 2025, significantly outpacing Gemini's 287 million visits, despite ChatGPT's declining market share. Different monetization strategies are emerging among the platforms. OpenAI offers various subscription tiers for ChatGPT, while Google has denied plans to introduce ads within Gemini. xAI provides free access to premium features in Grok, and Microsoft bundles Copilot with its software suite. The competition is also affecting marketing metrics, with AI-driven traffic converting at much higher rates than traditional channels, although such traffic remains a small fraction of total site visits. There are challenges for marketers as they adapt to the different citation practices and algorithms used by each AI platform.