There has been talk about a possible antitrust investigation into Google by the FTC for over a year. Earlier this year, the FTC hired Beth Wilkinson, a high-profile antitrust litigator, which many assumed signaled that this scenario would soon come to fruition, though FTC Chairman Jon Leibowitz brushed of the notion. He has, however, indicated intent to find a Section Five case.
CNET's Declan McCullagh has put out a rather interesting article, sharing some words from the Commission's former chairman, William Kovacic, who says though the FTC might try going after Google, it would be an uphill battle. He reportedly discussed this at the Technology Policy Institute.
He's quoted as saying, "The last time the FTC prevailed in the federal courts in a standalone Section Five case was 1968. That's a while ago. Not for want of trying, either. And one of the crippling limitations has been the (FTC's) failure to define in a meaningful way what the key operative criteria of that standard are."
You can read more about Section Five in this paper from AntitrustInstitute.org (pdf).
The point is, though the FTC might pursue antitrust litigation against Google, the former Chairman thinks it's a longshot that the FTC would come out victorious.
Of course, the FTC has come out victorious against Google in other ways recently (and has even gloated about it). The organization handed Google it's largest fine for a single company ever, in a settlement over privacy issues related to user tracking in the Safari browser.
Google has also faced antitrust issues from other governments.
Interestingly, Expedia, one of the companies that make up the FairSearch Coalition, a large proponent of antitrust litigation against Google, is finding itself embroiled in an antitrust suit of its own (though there are about 15 other companies involved).