It's been eight months since Kayak filed its registration statement for an IPO and there have been five amendments in the interim, but Kayak has yet to become a public company.
So, what's the deal?
In contrast, HomeAway filed its S-1 registration in March and a little more than 3 months later it was happily frolicking AWAY on Nasdaq.
In a PhoCusWright analysis in early June, prior to the HomeAway IPO, Tim Mullaney opined that the HomeAway IPO likely would be the easier of the two to execute largely because HomeAway faces less competiton and "HomeAway's prospective investors have no reason to fear that Google's merger with ITA Software will mess with its business model -- a question Kayak will face despite the favorable conditions regulators placed on the merger."
Indeed, the Google-ITA Software mashup still weighs heavily on the still-not-out-of-the-gates Kayak IPO.
There are two primary concerns for Kayak regarding Google-ITA Software.
First, Kayak's QPX contract with ITA Software expires on Dec. 31, 2013, and Kayak would love to show the market that it has concluded a long-term renewal with ITA Software.
The Google consent decree with the U.S. Department of Justice mandates that ITA Software renew contracts with existing clients, such as Kayak, on commercially reasonable terms.
But, there's still a lot of wiggle room in what those commercially reasonable terms would be and so far there has been no renewal.
Kayak is believed to be trying to get a new deal with ITA Software, but so far it has nothing to show for its efforts.
And, that's an uncertainty that no company wants when trying to pull off an IPO.
In its financial filings, Kayak notes its ongoing concerns:

Although the consent decree requires Google to renew our existing ITA agreement on the same terms, if ITA or Google limit our access to the ITA software or any improvements to the software, separately develop replacement software to which they claim we are not entitled or increase the price we pay for any improvements of replacement software and we are unable to replace ITA’s software with a comparable technology, we may be unable to operate our business effectively and our financial performance may suffer.
Second, Kayak apparently believes that it would be prudent to wait for Google-ITA Software to unveil their new flight-search product before pricing the IPO.
After all, that Google-ITA Software flight-search offering is another gigantic elephant in the room.
Kayak believes it can compete with Google on flights, but its arguments might have more credence once the curtains are opened on the Google-ITA Software product.
TechCrunch reported in early July that the Google-ITA Software flight search offering could be arriving "within a few weeks."
If those few weeks drag on into months, the timetable could be problematic for Kayak's IPO.
Despite all of the concerns, Kayak is believed to be resolute in its hope to join HomeAway on Nasdaq as KYAK.
Meanwhile, as Kayak grapples with its Google-ITA problem on the domestic front, other metasearch and online travel agency players internationally may be one day pondering similar issues as Google considers how to take its ITA prize global.
Kayak didn't respond to a request for comment.