Bugged in what way exactly?
As for new steppings, that is pretty common.
poor ram support, from the tweet it fixes the SOC which is why ryzen struggles with decent ram speeds, even more so when using 4 sticks.
uncore is also related to memory latencies
basically take the current ryzen as a beta test and this new stepping as the final revision .
they seem to think it's fixes several hardware level issues, which is probably why some rare chips can run 3600 but plenty can't get past 2666 ram for example