Good wine, as +Robert Iles
says ;), has depot in the bottle and shaking the bottle will mix it in the wine which makes the wine taste bad. There is also considerations on very high quality wine that if shaken it will mix with the air in the bottle too, therefor increasing the oxidation and changing the taste.
I hope I'm clear because my french is better than my english on the subject.
Oh and I must say : DON'T try it with champagne unless you share the video on Youtube ;)