This week brought a few noteworthy items from Southwest Airlines. First, they announced their frequency and city selections for all 18-slots they leased out of Newark Liberty International Airport (EWR). In August this year, Continental and United satisfied antitrust regulator concerns about their merger by granting 18 of their coveted EWR slots to fare-war-favorite Southwest. They will begin with Chicago and St. Louis service in March, followed by the full schedule in June 2011. Here’s how it will look at that time:

Next, it has been speculated for some time that Southwest is interested in serving the Hawaii market, and that speculation has pretty much given way to reality this week. CEO Gary Kelly announced the carrier will be taking delivery of its first 737-800 ETOPS aircraft in March of 2012. Additionally, they posted a job opening looking for an ETOPS program manager, who will be responsible for the process of earning certification in “extended twin-engine operational performance standards†over water.

Separately, but also expansion related, Southwest announced their plans to acquire AirTran Airways earlier this year. Still pending government approval, this effectively buys their long-missing presence in Atlanta, but also throws a wrench in their common-fleet strategy. AirTran operates Boeing 717 aircraft (really “DC-9sâ€) and also offers two-cabin aircraft. My prediction here is that Southwest will sell-off the 717s and eliminate the business class cabin.

Mexico is likely next on their radar, especially given the bankruptcy of Mexicana Airlines earlier this year. Having studied airline management, I have to say I’m incredibly impressed with Southwest’s performance this last decade, and their now more aggressive expansion plans. Herb must be proud!