Trax,
Seeing that I grew up in Boston it has my vote. Although I myself love going up to Montreal. They always say the grass is greener
Boston in Aug will be great no doubt about it. Quincy Market, Faneuil Hall, The aquarium, Newburry street, Harvard Square, North End, The Park. That time of year you can do a duck tour
www.bostonducktours.com
Let me know what kind of activities you are interested in and I will think of more things for you to do as options.