New York--Dueling technology portals CNET and ZDNet, both San Francisco, made gains in unique visitors in December, according to the latest figures from Media Metrix, New York. CNET's traffic grew slightly, rising to 9.65 million visitors from 9.40 million in November, a gain of about 3%. CNET stayed steady at 15th place on Media Metrix's unique visitors ranking. Meanwhile, ZDNet experienced more pronounced growth, with unique visitors climbing to 9.61 million from 8.87 million in November, a bump of 8%. ZDNet moved up to 16th place from 18th in November. Both tech portals are currently running advertising campaigns. CNET said it plans to spend $100 on a campaign that began in July. ZDNet said it plans to spend $25 million on a campaign it launched in December.