What is your "take-away" from the events in Boston?

I was surprised to hear a rational friend say she was debating about a trip to Boston next weekend. Do you feel that Boston is a less safe place now? Are you worried about being in large public places? Even more to the point, do you think these were the actions of two disaffected men, like a Columbine, or a planned terrorist activity? And does that affect your reaction? And should we all then have even more access to weaponry or should it be more restricted?