^Not quite. They only made it to Greenwich CT, 180 miles from Boston. A trip like that should be a lot easier once the Supercharger infrastructure is filled out.
It does raise the question: which is faster, driving at high speed and charging a bit longer or driving more slowly and cutting down the charge time? There must be an optimum speed for a given set of conditions, say: bottom half of the battery, the power available at the next Supercharger station, on relatively level terrain in mild weather. Someone here must have done the experiment.