Yonkers, N.Y.--ConsumerReports.org said Wednesday that it has attained 600,000 Web subscriptions since its launch in 1997. The consumer publication's ability to generate subscribers is of interest to b-to-b marketers, since early attempts by b-to-b trade publications to charge for online subscriptions failed. The publisher charges $24 a year or $3.95 a month for its product. Some analysts predict that b-to-b Web content will increasingly go the subscription route, or on a "pay-per-play'' basis for high-end information services. Today, many publishers depend on Web banner advertising, e-mail newsletter sponsorships and e-mail list rental for Web dollars.