If your travel is within North America, it's definitely Jetblue by a mile for me. Guaranteed free fast wifi access + satellite TV on board along with 32+ inch pitch, 18 inch wide seat. That pretty much makes the entire flying experience domestically at least enjoyable. And they fly to most domestic places I care to travel to. If they start flying mint to Europe in a couple of years, I'm going to be on there for a lot of long weekends.

Until then, I got exp on AA this year due to international traveling, so by default I'm going to fly AA most of the time. Even so, my domestic flying experience has been really impacted the times I don't get upgraded. At least internationally on the 772s out of JFK, the MCE are 9 across with 36 inch pitch and good recline. Before we get premium economy here, that's probably the most comfortable you get without splurging for business class.

I don't get the love for Delta at all, especially since you can easily get stuck on an old aircraft with narrow seats, no IFE or wifi.