FYI: ESPN's coverage of this is way better than the broadcast or cable news networks. They interviewed an employee who was 1.5 miles short of the finish line when it happened, an employee who had finished an hour prior to it happening and was in the medical tent just past the finish line getting treated for dehydration when it happened, and they also interviewed a woman who was literally 10 feet from the finish line (and thus 20-30 feet from the first bomb) when it exploded. Great first-person accounts from several angles.