Hi, I've just come back from NY, travelled with 18 month old ds and had a wonderful experience.
On arrival, immigration officials let you jump the queue if you have children (if they don't see you, don't be afraid to ask the queue attendant)
People where incredibly friendly everywhere I went to and went out of their way to help me/compliment ds.
One thing though: tried to buy cold medicine for ds and was told they DO NOT sell any medicine for under 2s without prescription, so make sure you take plenty of what you might need.
Hope this is useful.