I have a relatively large "vibe coded" project that I let Claude 4.5-4.7 drive over the past few months, and my read on it is:

1. It's much more verbose about how it perceives the current state of things, i.e. "this is a large, well-documented project"

2. It's much more willing to trust its own judgement, e.g. fewer prompts to approve decisions

3. In terms of how long it takes to solve isolated problems, and the quality of solutions it proposes, it isn't meaningfully different from 4.7

YMMV, and maybe my view will change as I work with it more, but it feels like system prompt tweaks more than a real step forward