Fetching from the wire…
01
02
03
04
05
06
07
08
Public story · 2026-08-05 · high
Apps pinned to the alias inherited a new model with no opt-in, and response time nearly halved.
Why now: The swap landed on August 5, the same day xAI published the announcement citing Artificial Analysis' benchmark comparison against GPT-Realtime-2.1 and Gemini 3.1 Flash.
xAI swapped the model behind grok-voice-latest on August 5, replacing Think Fast 1.0 with 2.0 for anyone pinned to that alias, per xAI. Pinning to that alias means always running xAI's latest voice model, not a fixed version.
Developers building voice features on that alias got new latency and cost behavior with no upgrade prompt. First-audio response time dropped from 1.25 seconds to roughly 0.70 seconds. Anyone who tuned prompts or timeouts against the old model is now running against different numbers.
Think Fast 2.0 scores 82.9% on Artificial Analysis' speech-to-speech benchmark, up from 75.7% for 1.0, per Artificial Analysis figures cited in xAI's announcement. That puts it ahead of GPT-Realtime-2.1 at 79.1% and Gemini 3.1 Flash at 69.5%.
Median reasoning-token use falls to 0.4x the prior baseline, and audio still costs $0.08 a minute. The model reasons in parallel with speech, so tool calls typically fire before it finishes its first sentence, per xAI.
Each link below shares sources, entities, or timing with this story.
Codex competes with Gemini / Shared entities / Earlier coverage
Linked by a graph relationship (Codex competes with Gemini); both cover Artificial Analysis, Flash, Gemini, GPT; earlier Artificial Analysis coverage from 2026-07-31.
Gemini built by Google / Shared entities / Shared topic / Earlier coverage
Linked by a graph relationship (Gemini built by Google); both cover Flash, Gemini, GPT; overlapping topics (benchmark, flash).
Gemini built by Google / Shared entities / Shared topic / Earlier coverage / Tension
Linked by a graph relationship (Gemini built by Google); both cover Flash, Gemini; overlapping topics (fast, flash).
Gemini built by Google / Shared entities / Shared topic / Earlier coverage
Linked by a graph relationship (Gemini built by Google); both cover Flash, Gemini; overlapping topics (against, benchmark, flash).
Gemini competes with ChatGPT / Shared entities / Earlier coverage / Tension
Linked by a graph relationship (Gemini competes with ChatGPT); both cover Flash, Gemini, GPT; earlier Flash coverage from 2026-03-17.
Gemini built by Google / Shared entities / Earlier coverage
Linked by a graph relationship (Gemini built by Google); both cover Flash, Gemini, GPT; earlier Flash coverage from 2026-05-16.
Simon Willison uses Gemini / Shared entities / Earlier coverage / Tension
Linked by a graph relationship (Simon Willison uses Gemini); both cover Flash, Gemini, GPT; earlier Flash coverage from 2026-07-23.
Cursor supports Gemini / Shared entities / Shared topic / Earlier coverage / Tension
Linked by a graph relationship (Cursor supports Gemini); both cover Artificial Analysis, GPT; overlapping topics (benchmark, call).