Still tops, but more delays
I'm a fan of Southwest on the bases of their on-time scores, low lost luggage rates, I-can-do-it staff attitude, and overall cost. The queue system for seating doesn't bother me and I find it worth the Early Bird fee to get on a bit sooner. The math is that it's a very effective way to administer a variable demand system.
My only knock is that after many flights with no delays, I've seen three delays on recent trips. We ended up making up some time in the air on two of those flights, which is cool. Just hoping it's not a pattern.