I have had afternoon tea at the Four Seasons George V and at the Crillon amongst the venues mentioned. Between the two, the George V offers much more polish and better service overall and would be my choice. It is usually busier and also more expensive than the Crillon. A macaron at the George V will run you 9 Euro at least. Full tea is in the 40 Euro range IIRC. There is live piano music as well.

However, at the Crillon, the "room" is very intimate, just off the main lobby and the furniture is very regal, done in royal blues. While the George V feels like one is having tea in a VERY posh Parisian apartment or in a very riche chateau in the countryside, the Crillon evokes the feeling of a palace, which it formally was. The advantage here is the live harp music which is beautiful. While the tea is good, the service is inattentive and the quality is decent.

May I also recommend a tea at Angelina? It is, IIRC, right by the Meurice, facing the Tuileries. I would also recommend tea at Marriage Freres, with the Marais (Rue de Bourg Tibourg) and the Left Bank, Rue des Grands Augustins having the most charm. The shop in the Faubourg St. Honore, close to L'Angle du Faubourg and Cave Taillevent (on the Arc de Triomphe side) is convenient if you want a 1-2-3 punch buying fine wine, chocolates and tea in one place as Cave Taillevent, and a couple other wine stores, are just down the street, and La Maison du Chocolat is right across the street. At Marriage Freres, you can try a pot of a remarkable selection of teas, many of which are not available at the hotels. They also serve food to go with the tea as well. I highly recommend this as an alternative to the high priced teas in the hotels.

Laduree, in the Rue Royale (IIRC) is great, if you can get a table as it seems to be particularly popular. Their Mont Blanc dessert is divine.

Cheers,