What people don't seem to realize (and I'm guessing it's because they haven't flown SW since the boarding change) is that there is no longer the "mob boarding" and waiting in line for 2 hours before your flight. You are now assigned a letter and corresponding number for your flight based upon your check-in time. They now how "posts" that show, for example, number 1-5, 5-10, etc, and you line up according to the letter that they announce at that time, and then within your number group. You'd be surprised at how much nicer this is than the other airlines. And although I fly SW normally, I've flown lots of the others recently taking my dd to visit her dad in Chicago. So I've experienced them both. Yes, it's nice to get an assigned seat so that I know where both my dd and I will be sitting, but in 50+ times of flying SW with her, I've never had an issue finding us seats together. Of course, we always check in at the 24 hour mark (only once have I paid for early bird check in). I also love the fact that they've never once changed our flight times once they're posted, and their customer service has been second to none.
Granted, I'm sure that I'd be just as upset had Airtran bought out SW, so I really do feel for all of you that are losing your favorite airline. I just hope that you'll give SW a shot if you haven't already.