CALIFORNIA - Personal video recorder pioneer TiVo, whose technology allows TV viewers to skip commercials, has launched Product Watch, a service offering on-demand ads to its subscribers.
   The company has signed up about 70 marketers, including Kraft Foods and General Motors, who will offer longer ads that attempt to be more informative than typical commercials.
   TiVo users will be able to search for ads in several categories, including finance, lifestyles and travel and leisure.