I'm based in HPN.

Years ago, White Plains/Westchester County airport had very high fares. These days, thanks to Northwest, many of the airlines offer competitive fares... or lower fares than JFK/LGA.

UA flyers have mixed odds on flying a 170 to ORD.
Headed to IAD and you'll fly a regional jet.
Routing through IAD does offer more miles than transiting ORD.

It's a pretty airport. About 15 years ago, it was an old W W II quonset hut, and looked it.
These days, with jetBlue and Air Tran, we're a crowded airport.
There is limited bus service to downtown White Plains, where you can take the railroad into the city (that's Manhattan). The trip from HPN to WP is 15 minutes, and the railroad is 32 - 48. Local vs express. FYI, if you have a very early flight out of, or a late inbound, you're SOL on the bus. Do not, whatever you do, take the car service located in the baggage area. They're expensive. Call the local WP taxi (Splendid) at 914 682-2222.

In bad weather, especially when there's fog, HPN shuts down. In the early 1980's, 2 or 3 private jets went down.