I have been asked when is the best time to trade in the forex market. That is similar to asking when is the best time to exercise. Some people like to exercise in the morning and watch the sun rise, others like to go to the gym during the best meat market times and flex in the mirror. It comes down to preference and what you are trying to accomplish.
My preferred trading times are between 8am - 11am EST for scalping/intraday trading and around 5pm-8pm Eastern. The earlier times gives me the best volatility for the scalping and the later times gives me the quietest market to plan the longer term, multiple day trades (the price action from news is already shaken out).
This is just my view, what's yours?