Brian Sumers

If Virgin America was not expected to merge with Alaska Airlines, analysts likely would fret about Virgin America's falling unit revenue. But since Virgin America is now in limbo, waiting to see if it can close its merger, it's not clear how much the unit revenue decrease matters.

Lufthansa Group is about a decade late in realizing the European low cost carriers are a massive threat. But it's good to see the company trying to do something about it and expanding its Eurowings operation.

In most cases, airlines have the technology to give passengers more control over their journey. Carriers should take advantage of this, and they should start by making their mobile apps a lot more useful than they are today.

Allegiant has been busy with other matters in recent years, but the airline should once again focus on selling vacation packages. The margins on hotel rooms, rental cars and attraction tickets are usually much higher than margins on airfares.

Southwest is almost a victim of its own success. Investors have massive expectations for the stock, and since Southwest is now performing no better than the competition, the company is losing its luster a bit. But the airline should be OK.

Under new CEO Bob Fornaro, Spirit Airlines is deviating slightly from the typical ultra low cost carrier playbook. Most passengers probably won't notice it, as Spirit will still pack in the seats and charge for everything. But around the edges, Spirit's strategy is evolving slightly.

JetBlue's investment in JetSuiteX is probably not a game-changer. But it is unusual, and it will be interesting to see how the JetBlue/JetSuiteX partnership evolves.

American, United, and Delta are all introducing no-frills fares to try to thwart Frontier, Allegiant, and Spirit. It might work, or it might not. But it's worth a shot. The Big 3 do not want any of the discount airlines to grow to be as large and powerful as Ryanair.

The important stuff is happening in Washington, D.C. where the Department of Justice is considering whether it will seek to block the Alaska Airlines/Virgin America merger. This is more of a minor hiccup, but it's undoubtedly annoying for the two airlines.

It's a short reprieve, but this is good news for travelers. For the next couple of months, they can buy the cheapest tickets on American and United and still get all the perks that the airlines offer to customers who buy pricier tickets.