I'll add my two cents.

Favorites:

BWI - I don't love it, but it's by far the most convenient of the three D.C. area airports for me. I can leave my house exactly one hour before my flight departs, which is definitely nice. I agree with the previous poster who said it looked very 1980s. I remember flying from ISP to FLL in the late 80s as a kid and connecting at BWI (on Piedmont Airlines) and remembering the bright red columns. It always looked very space-agey to me, at least back then. At least the security lines aren't bad like they used to be immediately following 9/11.

DCA - It's not as convenient for me anymore and the security lines are a pain, but you can't beat the view the access via Metro.

MHT - This is probably my favorite small airport. I love having the car rental facility so close to the airport.

MSP, PIT - Great airports for making connections. Love the WiFi service.

ANC (new terminal) - New terminal (C) is very modern and easy access to rental cars plus the feeling of being in Alaska.

SAN, SLC, FLL, SEA and LAS I like because they're convenient to the cities they serve.

Other small airports I like: PVD, PBI, BDL, BTV, ISP (new terminal)

Least Favorites:

IAD - I will do anything to avoid this airport. Everything about it is inconvenient - the access to the airport itself, the terminals, etc.

OAK - The AirBart service has got to go. I prefer BART to SFO anyday.

PHL - Feels like a bus station

LAX - T1 security lines...

SJC - One terminal feels like it's a temporary trailer, the other (Southwest) is just plain cramped.

DEN and DFW I don't like because of how far they are from the cities they claim to serve.