Mark Zuckerberg unveiled Meta's latest artificial intelligence model, Muse Spark 1.1, on X rather than the company's own platform, Threads, prompting Elon Musk to seize on the decision with a sarcastic one-line response. The Meta chief executive introduced the new agentic AI and coding model alongside the Meta Model API in a series of posts on X, describing it as a low-cost model built for coding, tool use, computer interaction, and long-running tasks, supporting a one-million-token context window. Although Meta has not commented on why Zuckerberg used X instead of Threads, the decision became part of the story after users questioned the bypass. Elon Musk fueled the discussion by arguing that X remains the best platform for CEO-led product announcements, pointing out that Zuckerberg's post had already attracted more than 12 million views without paid promotion. The platform choice sparked wider debate over whether X holds a stronger position than Threads among developers, technology investors, journalists, and the broader AI community, reviving the long-running rivalry between Musk and Zuckerberg.