That's somewhat surprising, said Forrest Morgeson, director of research for ACSI, in that mergers have historically wreaked havoc on satisfaction as carriers try to consolidate operations and coordinate systems. "We're not seeing that in the latest mergers," he said. "American, for example, has been going a little slower [with its purchase of US Airways]; that kind of strategy may prevent the satisfaction dips we've seen in the past."
Meanwhile, the airlines are doing a better job of getting us there on time and handling our baggage. It's the onboard experience that's lagging. Not surprisingly, seats remain the worst part of flying.
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"Seat comfort is by far the lowest scoring element of the entire experience and that's unlikely to change," VanAmburg told NBC News. "We don't like it, but it's something we've learned to live with."
Then there's what happens after you reach your destination. The hotels category was unchanged at 75. Online travel agencies (OTAs) edged up 1.3 percent, to 78. High-scoring hotel brands included Homewood Suites by Hilton (83), Grand Hyatt (83) and Hampton Inn (81). Not surprisingly, perhaps, travelers who paid the least were the least satisfied with Motel 6, Super 8 and Econo Lodge all scoring 63 or less.
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The report also noted staff courtesy has dropped from a year ago. And guests are often unhappy with the "free" WiFi service they get in their room.
"If it's free and it doesn't work well, you're going to irritate customers," VanAmburg noted.
Among the OTAs, the major players were all within two points of each other but trailed the "All Others" category, which includes both smaller startups and the airlines' and hotels' proprietary sites. According to Morgeson, recent mergers, such as Expedia's purchase of Orbitz and Travelocity, aren't expected to impact satisfaction levels but all three will likely face increasing pressure from both more nimble startups and direct-supplier sites.
On the other hand, the OTAs still outscore hotels and especially airlines.
"While there is some improvement from a year ago, it's important to note that airline satisfaction is still very low," said ACSI director David VanAmburg. "In fact, among the nearly four dozen industries we rate, only a handful rank lower: health insurance, cable TV and Internet service providers."
—Additional reporting by Herb Weisbaum.