The main change is the addition of 3 new types of UUIDs:
UUIDv6 is an improvement of v1 where the timestamp has been reordered in a way that prevents index fragmentation issues.
UUIDv7 is mostly composed of the timestamp in milliseconds followed by random data. As for v6, the timestamp prevents index fragmentation issues, which makes v7 a great replacement for v4 and Ulid.
UUIDv8 is the DIY version of UUIDs, it's almost only custom content. If none of the other versions suits your needs, this is the one to use since you get to decide what's inside (except for the version and variant fields of course).