Re: Business travel between Washington, DC and New York City
 

Acela and it's not even close.

LaGuardia is the King Shithole of Shithole airports

Re: Business travel between Washington, DC and New York City
 

a) Delta takes off every hour. It takes off ON the half-hour.

b) The Washington Post did a big feature on the merits of the train, shuttle, and bus to DC. you might find it if you google it, though it's kind of an old story

c) Depending upon when you get your plane ticket, it will be cheaper than the Acela, even factoring in the cab to LaGuardia.

d) All in all, having done both many, many times, it's very close. In perfect weather, I prefer flying. If there's a chance of rain or snow, I prefer the train.