Here is my first assessment of Sonnet 5:
Sonnet 5 is better than Sonnet 4.6. Who would have thought? But jokes aside: Unfortunately, it is weaker than Opus 4.8 across all evals. Why they nevertheless labeled the latest Sonnet 5 iteration with a “5”, even though “4.8” would have been more fitting, is beyond me. Normally, major version jumps in particular signal a significant leap in capability. Be that as it may: Sonnet 5 is good, but worse than expected.
Pricing has not changed; it is on the same level as its predecessor. Opus is still more expensive, but at the same time it also remains better. Overall, the release irritates me and leaves more questions than it answers.
I cannot help but see Sonnet 5 as a release that stands in the context of Fable 5. There was no mention of Fable 5 at all, which surprises me a lot. I really would have expected us to get news about it at the same time. But nothing. Instead, we get an update to a new model series (“5”), but one that is not significant compared with the models we already have.
As a result, there is a lingering aftertaste that Sonnet was released as something in between, perhaps also simply to release something at all and to stay part of the conversation, including in a positive sense. Why no Opus 5, when we know that Fable 5 already exists as a model that performs significantly better than 4.8, and when we can assume both that a better Opus exists internally and that it would not be difficult to update Opus to the new generation? Why “only” Sonnet 5?
Because restraint is currently required. The major releases are currently being delayed across the board; they are still in discussions with regulators about how the truly powerful frontier releases can be carried out at all and under what conditions. In my view, the Sonnet 5 release has to be seen against this background. And as a result, at least for me, it was disappointing overall.
Honestly, I no longer believe that people outside the U.S. will still have access to frontier models, and even there, access will be limited.
We are now witnessing the end of public access to frontier intelligence.
It is a very sad and serious turn of events.
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