A WebmasterWorld thread reports a change to the Yahoo Search Marketing terms of service. The change basically says that Yahoo can add or edit your ads and you must pay for the clicks on those ads. Here it the legalize:

Read that carefully.

Yahoo “may help you optimize your account(s).” You “expressly agree that we [Yahoo] may also: (i) create ads, (ii) add and/or remove keywords, and/or (iii) optimize your account(s).” Not only that, “you remain responsible for all changes made to your account(s), including all click charges incurred prior to any reversions being made.” Yes, you are responsible for the changes Yahoo makes.

Crazy stuff and the forums are buzzing about it right now.

Forum discussion at WebmasterWorld and Search Engine Watch Forums and Sphinn.