San Francisco--ZDNet, Ziff-Davis' online technology portal, on Monday launched a redesign, which is intended to make it easier for users to navigate the 60 Web sites in the network. The redesign includes a unified look to the network's sites. More important, the more than 30 channel headings previously found on ZDNet's home page have been reduced to 10 categories: tech news, reviews, shopping, business and technology, help and how-to, downloads, developer, investing, games and tech life. Users can still search content by publication, clicking, for instance, on PC Magazine or Yahoo! Internet Life. ZDNet is locked in a marketing battle with CNET, which launched a $100 million marketing campaign in July. While ZDNet continues to advertise in Ziff-Davis publications and other media, it has focused on keeping the visitors it has and on the ``stickiness'' of the sites. In September, the ZDNet sites ranked 15th in unique visitors, with 8.6 million, according to Media Metrix, a New York-based Internet ratings service. In September, CNET ranked 17th with 8.3 million unique visitors, according to Media Metrix.