jetBlue and US Airways are the difference between night and day. US Airways has started charging for everything including soda. Some of the US Airways aircraft are so dirty and so old and the crews seem miserably unhappy (not that you can blame them). jetBlue, our hometown airline, is opening a new terminal at JFK Airport which will be a destination unto itself with fine dining. jetBlue flies brand new planes and they all have wonderful in-flight entertainment, they have DirecTV. US Airways doesn't even have audio, they're removing the movies on the long haul flights. It really is like trying to compare Beverly Hills with the poorest neighborhood in Brazil, which is better.
I prefer JFK Airport because I can take the JFK Air Train / LIRR and I can be in Manhattan in less than 45 minutes. Taxi's from JFK have a set fare of $45.00 plus toll and tip.
LaGuardia is a much older airport which is very delay prone. Nothing ever seems to arrive or depart from LaGuardia within an hour of its scheduled time. It is a very small and very old airport. JFK is much better, in my opinion.