beezerdave said:
This will be my first time on Southwest as well. Still a little cloudy on the whole A, B or C thing. Do I understand there is no assigned seating? You just kinda get on the plane in groups and play musical chairs?

Because I'm 6'3" I try to get an aisle seat or exit seat so I can stretch out a bit. Will I have trouble doing so?
Here's how it works. There are no assigned seats. First those who can pre-board board. This includes families with small children (under 4, I think) and those with medical conditions that got a pre-boarding blue ticket jacket from the gate agent.
On flights to/from Orlando, there can be a lot of pre-boarders. If you want the best seats - try flying at an off time.
Then the A group boards. The order within A is determined by a line at the gate. Usually, this line forms about 60-90 minutes before the flight.
Then the B group, then the C group. I believe these letters are basically evenly assigned. That is if the plane had 99 passengers, the first 33 to check in get A, etc.
If you check in online at about 24 hours before your flight, you should get A. If you wait until the morning of your flight, you'll probably get B. If you check in at the airport, you will probably get C.
If you do get an A, are at the airport early and don't mind standing in line, you can get close to the front of A. Now while there are a lot of pre-boarders, most of them are not eligible to sit in exit rows, so those very well may be available (and tend to have more space - check out seatguru.com for details - looks like seat 12F is the absolute best for leg room). Also, families tend not to take the bulkhead seats, which lack underseat storagem but have more leg room.