According to BTN's website they have 46,759 subscribers that spend 239 Billion dollars a year annually. My Dad is a subscriber. What ever the highest level of frequent flier status you can have with Continental is, he has it. I think that's the sorta person who reads and cares about that stuff. I think there is a difference between traveling on business and a business traveller. The business traveller spends money on travel as a cost of doing business. Traveling on business implies you just need to get from point a to b to get the job done. It really isn't realistic to compare the level of service offered by a legacy carrier to any of the LCC's. The LCC's will get a portion of business transports who are attempting to curb costs. But the airport clubs, first/business class and global reach puts the legacies in a different class of service.
I got to 1K status at UAL on business travel. But that was in a DoD position where the DoD negotiated bulk fares with the airlines. Since I was in DC and most city pairs had a UAL choice, I aimed almost all of my flying to UAL with AMR being my second choice.
That kind of model works fine for a large company with a lot of employees who travel.
In my brother's case, he does not have a large travel budget. He does not have the power to negotiate good rates with any airline because his employees don't travel very often - perhaps an annual product training event or conference for the employee. He also has very little turnover in spite of his stingy travel budget. Funny, his employees understand that if my brother pays a bunch of money for airfare and a hotel room, they won't get paid as much money. They prefer pay over preassigned seating and a nice hotel.
I find a comparison between Southwest and Major carriers to be apples to oranges. Frankly, I'm surprised that Southwest is even mentioned in the publication. I suspect that Southwest making the list is a recent phenomenom and instead of being dismissed, this should cause great concern among pilots at legacy carriers.