The proper temperature of the water depends on the type of tea.
Black, red and herbal teas can handle water at a full boil of 212°F (100°C). In fact, black teas especially need very hot water to help draw out the complex flavors of the tea.
Water for green and white teas should be at a light boil of 160-190°F (71-88°C). These teas can scald if the water is too hot. Fun fact: Two leaves headquarters is at an elevation of 6,611 ft (2,015 m) where water boils at around 200°F (93°C)!