Net Effect: The battle of the network sites overtakes in unique visitors during Feb.

NEW YORK -- NBC Universal and News Corp.'s new video site might significantly change the game in the network Web site battles, but until it debuts in the summer, and are trading blows in the race for top broadcast portal.

In February, saw a sizable uptick in unique visitors to finish the month with nearly 9 million uniques, according to Nielsen//NetRatings., which was first by a considerable margin in January, had slightly more than 8 million visitors for the month. and had 5.6 million and 2.9 million February visitors, respectively.

Bruce Gersh, senior vp business development at ABC Entertainment, and Alexis Rapo, vp digital media at ABC, said that streaming episodes of "Grey's Anatomy," which had a three-episode story line during the month, and Web features including a personality quiz around the primetime drama were the largest drivers to the site. "Lost," "Desperate Housewives" and "Ugly Betty" also were popular on

Vivi Zigler, executive vp digital entertainment at NBC, said that the network site's 13% drop-off from January was just a "natural fluctuation" and remains encouraged by her company's digital strategy. NBC said Thursday that it will be adding social networking capabilities to its site and will considerably expand features around "Heroes," which is the biggest driver of traffic to the site. "Studio 60 on the Sunset Strip," "Friday Night Lights" and "30 Rock" also performed strongly on the portal during the month.

A spokesman for CBS Corp. pointed out that it has deals with "dozens of partners," including iTunes and, to distribute online content outside of "Jericho" and Showtime's "Weeds" performed well online for the network during February, the spokesman said.

Fox declined comment on the findings.

Nielsen//NetRatings is owned by the Nielsen Co., parent company of The Hollywood Reporter.