Two local online advertising businesses--Westlake Village-based ValueClick, and Irvine-based Specific Media--are showing growth in the latest comScore ranking of advertising networks. According to comScore, which analyzes Internet traffic and e-commerce statistics, ValueClick is now number five, and Specific Media number six, in the top online ad networks--just behind Platform-A, Yahoo, and Google. comScore said that ValueClick grew 14 percent year to year in total unique visitors, to 160,307,000 total uniques for April, and Specific Media grew 9 percent, to 158,012,000 unique visitors for the month. The two are just behind Google, which had 164.5M uniques for April.