Artificial Analysis is out with Intelligence Index v5. Biggest change: 60% of the weight now sits on private test sets and held-out answers. So the public benchmarks everyone spent two years tuning against don't measure much anymore. Claude Opus 5.5 (max) is first at 58. GPT-6 Astra 57, GPT-6.1 Sol 55. Close at the top, at least for now. Open vs closed went from a 3 point gap to 12. Kimi K3.1 Pro is the best open model at 46 and the weights aren't out. The best one with downloadable weights, DeepSeek V4.1 Flash, gets 32. That's under Claude Haiku 5.5. Open weights aren't one tier behind anymore. They're two.
Artificial Analysis is out with Intelligence Index v5.