I can think of many arguments and grounds for where this practise should be found wrong. But then, I'm not the one who dips in court with the judge who can't be arsed to work much past lunch, due to his old act up as a law enforcer of the court. Welcome to a new kind of tension.

M R snakes
M R not
O S A R
C M B D eyes?
L I B! M R snakes

Does Google offer exclusivity on AdWords for an additional fee now?

Otherwise both Firm A and Firm B could shill for the same keyword and their ads would pop up side by side or in rotation (subject to the limits AdWords customers can set/impose).

Still, it's fun watching law firms lose their good judgment or otherwise have the free time to create test cases. Unless Wisconsin has some really interesting local law, it'd be hard to frame an AdWord as appropriation - http://en.wikipedia.org/wiki/Privacy_laws_of_the_United_States - and courts seem pretty conservative on the subject... but if the precedent does get set, Google's business model might take on a little water.)