There's good reason to take the recent threats of Islamic terrorism against New York City very seriously IMHO.
I believe there might have been an important reason for the following that traces back to the autumn 2001 Anthrax mailings:
As highlighted in the PBS Frontline episode, The Anthrax Files, the odds are the FBI never really caught the 2001 Anthrax mailer. The true culprit could still be at large. If so, let's all hope and pray he isn't connected to ISIS!
The NYPD and FBI might be on top of this, but, if past performance is a reliable indicator, then...
UPDATE: I just learned that Israeli Prime Minister Netanyahu is scheduled to speak at the U.N. tomorrow.
Anyone living or working in New York City should have a two-week supply of a broad-spectrum antibiotic on-hand IMHO. NYC authorities should have seen to this years ago, but I guess New Yorkers prefer not to think in these terms.
At the least, might I suggest New Yorkers avoid the subway system Monday and maybe next week altogether if they can at all do so?
I pray to my heavenly Father that my concern is unwarranted, and I apologize if so. Better safe than sorry. Beware New York City...