Why Weibo’s tiny VibeThinker-3B has the AI world arguing over benchmarks again

On Sunday, a team of nine researchers at Sina Weibo — the Chinese social media giant better known for its microblogging platform than for cutting-edge artificial intelligence — quietly posted a 14-page technical report to arXiv that sent shockwaves through the AI research community. Their claim: a language model with just 3 billion parameters can match or exceed the reasoning performance of flagship systems from Google DeepMind , OpenAI , Anthropic , and DeepSeek that are hundreds of times large