Los Angeles-based law firm Kabateck Brown Kellner filed a class action suit against IAC property Citysearch, alleging the site charges pay-per-click advertisers for fraudulent clicks. The firm has won similar cases against Yahoo and Google. All the major search firms now belong to anti-click fraud coalitions and make lots of nice noises about the problem. Truth is, click fraud isn't much of one. As Google CEO Eric Schmidt explained during an unguarded moment a couple years ago, click fraud will never be that much of a problem because if fraudulent clicks devalue the worth of click for an advertiser, that advertiser can always pay less per click.