Here are some photos from our recent trip to Boston/Cambridge. We had a wonderful time being tourists and averaged 10 miles per day on foot! It was a wonderful mix of history, excitement, and fantastic weather.
It was neat being in such a densely populated city where people really take pride in their surroundings. Most of Boston was incredibly clean and well kept. The locals were very friendly and far less "afraid" to come up and talk to a stranger than people in the mid-west, it was quite refreshing!
In short, if you haven't been, I would definitely make the trip.