Most likely the security fix that was issued recently for 16, which explains the small size.
So far, the only fix I’ve noticed has been the accessibility option to use personal voice (the keyboard initially covered the prompt, now it’s back to normal).
Yes, there is a new information button in Music that lets you see all the people that worked on a song. There are design changes in the mental health part of health, and a few other tweaks
Big thing seems to be that the hidden keyboard and PNG transparency bugs appear to be fixed.
So far, nothing noticeable, but it’s a bit more stable. I haven’t noticed the annoying iMessage keyboard issue, so that’s good!