Travel search firm Kayak is joining fellow New England companies Zipcar and Brightcove by filing for an initial public offering this morning. All three are slated for the first half of 2011, but Kayak has one rather large roadblock in his path other than the current market conditions.

Earlier this year, Google announced the acquisition of Cambridge Mass based ITA Software for $700 million in cash, but the deal is still pending. The travel industry is aggressively trying to stop this deal as it would give Google an extreme amount of control over the entire industry.

The four major online travel companies formed an alliance called FairSearch.org to try and persuade the government to block the acquisition under antitrust law. Kayak.com, Expedia.com, Travelocity.com, and Farelogix Inc. claim that ITA would give Google control over the software that powers its competitors and allow it manipulate the online travel marketplace.

According to an article on TechCrunch this morning, ITA’s Software powered 42% of Kayak’s overall airfare query so far this year. And according the filing, one of Kayak’s risks is that it depends on a third-party to query airfare results.

Kayak’s numbers from the filing are also very interesting. Revenues have grown 48% since last year, but net income is actually down in the first three quarters from $10.4 million to $6.2 million.

Here’s an excerpt of what Kayak said about the Google-ITA deal:

“If completed, Google could pursue the creation of new flight search tools which will enable people to find comparable flight information on the Internet without using a service like ours. According to Experian Hitwise, in September 2010, approximately 30% of travel searches began with Google. Upon completion of its acquisition of ITA, this number could substantially increase, as Google may choose to offer services that directly compete with the services we offer. Google may also cause ITA not to renew any agreements with us, or to renew agreements with us on less favorable terms. If ITA or Google limit our access to the ITA software or any improvements to the software, increase the price we pay for it or refuse to renew our contract and we are unable to replace ITA with a comparable technology, we may be unable to operate our business effectively and our financial performance may suffer.”

This will be a very interesting deal to watch as they are so many factors into whether Kayak has a successful IPO. As stated above if the Google-ITA deal goes through the travel industry could change immensely and competition could be reduced drastically, posing serious threats to Kayak.