Bloomberg Businessweek reported this in the last hour:
Hurricane Irene knocked out electricity to more than 900,000 customers from South Carolina to Maryland as the storm carved its way north along the U.S. East Coast, prompting Exelon Corp.’s Oyster Creek nuclear plant in New Jersey to shut.
Not a lot of details at this time. According to Wikipedia, Oyster Creek, located in Lacey Township, New Jersey, has a single 636 megawatt boiling water reactor. Coming online on December 1, 1969, the Oyster Creek nuke is the oldest commercial reactor in the United States.