I think ITA made a great deal of hype around their NP proof, but the complexity of the search was known by many and was known before ITA published their results. For example, Tom Holloran (United Airlines) published a paper at AGIFORS in the 1980's that showed the equivalence to a set covering / set partitioning problem.
Sabre's fare search engine was rewritten from scratch in C++ & Java starting about the same time ITA started. The search engine runs on a Linux cluster, and independent benchmarks show that it is the leader in finding the lowest fares. In fact, pretty much *all* the major players in fare search run on x86 clusters. You could look this up online too :-)