NetRatings, which measures Web traffic, is acquiring rival Jupiter Media Metrix in a deal worth about $71.2 million that will turn NetRatings into the leading Internet measurement and research service.NetRatings said the acquisition should nearly double its customer base. When the deal closes as expected in early 2002, Bill Pulver will become CEO and prexy for the combined company and Dave Toth, currently CEO of NetRatings, will leave to pursue other interests. Pulver is now prexy and chief operating officer of NetRatings. Jupiter has been struggling to stay afloat, after its merger with Web measurement service Media Metrix and the shuttering of many of its dot-com clients. New York-based Jupiter’s stock has been trading below $1 on the Nasdaq Stock Market.