I've seen New England and Manhattan, Azerbaijan, Cuba, Catalonia, seen Italy re-seperate, Flanders, Lithuania, and a couple sub-states in 1.3.
China split in half, with "Heavenly Kingdom" forming initially with just a few rich coastal states and basically getting into a prolonged civil war with the old empire, grabbing a few states with each treaty until they had 80% of China.
I have seen (without my own intervention)
Newfoundland
Quebec
Cuba
Azerbaijan
Zimbabwe
Flanders
Wallonia
Zanzibar
Philippines
Yea! Azerbaijan!
The Heavenly Kingdom? You mean Taiping? I thought they were not present in V2 in any form.