Seattle was given its nickname because of its lush greenery, not because of how environmentally friendly it is. But, I'd say it is true in both regards. Especially in comparison to the other American cities I've visited (I couldn't find a recycling bin anywhere in Boston so I brought all my recyclables home...), Seattle gets a A+ when it comes to being green.
Recycling bins were everywhere - on the street, in my hotel, in the train station, at the airport and on the ferry. It was just like being at home. Fresh local food is available in abundance at the famous Pike Place Market.
And public transit - at least in my limited experience in the downtown area - is fantastic. In the core you can ride FOR FREE between 6 a.m. and 7 p.m. The ferry to Bainbridge Island is inexpensive at only $6.90 and the quaint downtown is a five minute walk from the dock so no need for a car. The best part of Sound Transit is the direct link between downtown and the airport on light rail for just $2.50 one way. Wish we had something like that in Toronto...