I've just started using Googles PPC program and am becoming focused and concerned about 'click fraud'. Google, Yahoo, and the rest, really need to do something about this problem else their revenue generating model will go flat.
I don't think Yahoo is as vulnerable because they are more spread in their offerings than Google but we are talking millions of dollars here.
I just read this about one such case that Google is fighting:
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Advertiser allegedly abuses search engines
By David A. Vise
Washington Post
. . .according to a lawsuit filed last year by Google, is that Auctions Expert began clicking on the ads itself, artificially inflating the number of clicks and driving up the bills sent to advertisers.
http://www.fortwayne.com/mld/journal...s/11483443.htm
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Storms on the horizon?