But there are still another 500 or so cities with scheduled air service that do not have any low-cost-carrier competition, and these are the cities that will likely see significantly higher airfare prices in the long term. The reason: as mega-airlines attempt to hike prices systemwide (which they have already done several times this year), there will continue to be little or no competition to drive prices down, the kind of thing that occurs in the bigger, more competitive cities. This is already an issue today, but is likely to get worse as we have seen in the wake of other major airline mergers.
And that doesn't even take into account the different add-on fee structures used by United and Continental, but I can give you a hint on that: in situations where the two carriers have different prices for things like extra legroom, priority seating or pet transport fees, the one that will be adopted by the new mega-airline will be the higher one. Trust me.
The last area where we are likely to see significant price increases in the long run is on those coveted nonstop flights that make air travel so much easier, especially for business travelers. Mega-airlines, especially at their hubs, will be even more emboldened to charge hefty premiums on those prime flights because one less "connecting" carrier is in the mix.
As for frequent flier programs, at this point we just don't know what will happen when United and Continental are combined, but I suspect there will be some gnashing of teeth; the members of one program or the other are bound to be made unhappy (though a few will be happy if they are members of both programs and get their miles combined into one fat account).
What's next? United's previous "love interest" -- US Airways -- insists it can stand alone and keep flying, even as investors are pointing out to American Airlines that it might be time to double up with another carrier. But so far, it's just been talk and unsolicited advice.
But it will be kind of interesting to see how long this latest combo of United-Continental actually holds the title of "World's Biggest Airline."
This work is the opinion of the columnist and does not reflect the opinion of ABC News.
Rick Seaney is one of the country's leading experts on airfare, giving interviews and analysis to news organizations including ABC News, the New York Times, the Wall Street Journal, Reuters, the Associated Press and Bloomberg. His Web site, FareCompare.com, offers consumers free, new-generation software, combined with expert insider tips to find the best airline ticket deals.