Good copying: Taking something that came before and looking at it from a new angle, using it as inspiration for something unique, creative, and awesome.
Bad copying: Taking something that came before and trying to pass it off as your own.
(By the way, after Conan called out Da Peng, the Chinese show responded with an apology as well as a bit of taunting Conan’s way. Conan then made his own apology and even created a new version of the opening specifically for the Da Peng show, which they are now using. Glad they were able to bury the hatchet before things got serious.)