Not exactly a toning shoes issue, but Vibram Five Fingers have had a class action suit filed against them that has all the hallmarks of the Reebok settlement with the Federal Trade Commission and the class action cases filed against Skechers. Vibram Five Fingers are a minimalist running shoe offering no support or cushioning. They are very popular with the barefoot and minimalist runners. The suit alleges that the health gains promised by wearing the shoes did not eventuate. Vibram have issued a statement denying the claims and stating they will vigorously defend them

Link to the suit.
Runners World’s legal analysis of the suit.
There has been a lot of online discussion and debate about the merits of the case (eg see: Vibram Five Fingers facing class action over health claims).

There is a good analysis of the more recent unsuccessful attempt attempt by Vibram to get the case dismissed here.