Dallas Area Rapid Transit (or DART) commuter rail will also begin serving DFW sometime this year. "The DART Orange Line will run from downtown Dallas to DFW Airport, marking the first passenger rail service to the airport," said DFW spokesman David Magaña.
At $4.1 billion capital improvement program is underway at Los Angeles International Airport. The centerpiece of that project, the $1.9 billion renovation of the Tom Bradley International Terminal, opened in September 2013 and renovations are underway in Terminal 5.
In the New York area, there have been recent major upgrades in Terminal 4 at Kennedy International Airport, but the major project for the Port Authority of New York and New Jersey is a $3.6 billion replacement of LaGuardia Airport's Central Terminal Building, which first opened in 1964.
(Read more: NY-area airports lag in passenger amenities: Study)
"It really is the terminal that drags down the reputation of LaGuardia and is the embodiment of how people think of the terminals at NYC-area airports in general," said Steve Sigmund, executive director of Global Gateway Alliance, a group advocating for improvements to the NYC-area airports.
In Florida, a $1.1 billion plan is just beginning at Orlando International Airport to modify and expand a wide variety of existing facilities by 2017. Upgrades include the addition of four international gates, improvements to the ticket lobby and construction of an automated people mover and rail center.
Earlier this month, design plans were released for a new North Terminal at Louis Armstrong New Orleans International Airport that will have two concourses, 30 gates, a consolidated checkpoint and a garage with 2,000 parking spaces.
The $826 million project is slated to be completed by 2018 and was described by New Orleans Mayor Mitch Landrieu as "the most transformative project for New Orleans since the Superdome." Also included will be a power plant and on-site hotel.
"Tired, dated terminals are gradually disappearing and going the way of the Dodo bird," said Mary Kirby, founder and editor of the Runway Girl Network. "In their place, passengers will increasingly find bright, sparkling new facilities bursting with concessions and, of course, an ample amount of retailers."
These changes are not only welcome for travelers, said Kirby, but also essential from a competitive standpoint.
"Airports and airlines are keenly aware that passengers are mobile, vocal and social, and it's imperative that the 'passenger experience' be considered in all terminal projects going forward," she said.
—By Harriet Baskas, special to CNBC.com. Baskas is the author of seven books, including "Hidden Treasures: What Museums Can't or Won't Show You," and the Stuck at the Airport blog. Follow her on Twitter at
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