Google announced that it has signed an acquisition agreement with ITA Software. Reports of talks surrounding such an acquisition were revealed in April, but talk heated up again this week, mostly regarding issues of concern expressed by many in the travel industry.

Marissa Mayer, Google’s VP, Search Products & User Experience, has now posted to the Official Google Blog that an agreement has been signed. She writes:

Today, almost half of all airline tickets are sold online. But for many people, finding the right flight at the best price is a frustrating experience; pricing and availability change constantly, and even a simple two city itinerary involves literally thousands of different options. We’d like to make that search much easier, which is why I’m pleased to announce that today we have signed an agreement to acquire ITA, a Boston-based software company specializing in organizing airline data, including flight times, availability and prices.

While online flight search is rapidly evolving, we think there is room for more competition and greater innovation. Google has already come up with new ways to organize hard-to-find information like images, newspaper archives, scholarly papers, books and geographic data. Once we’ve completed our acquisition of ITA, we’ll work on creating new flight search tools that will make it easier for you to search for flights, compare flight options and prices and get you quickly to a site where you can buy your ticket.

I can’t imagine that Bing is incredibly thrilled with this news, as its travel offerings have been one of it’s largest selling points. One can hardly imagine that Microsoft didn’t see something like this coming though.

The deal is for $700 million, subject to adjustments (this is a bit less than the originally rumored $1b). Google says it intends to honor existing agreements ITA has in place. More details about the acquisition can be found here.