“Green sites earned the #1 spot on the top gaining categories ranking in March — a result of Americans seeking ways to cut back on energy consumption beyond Earth Hour amid a backdrop of skyrocketing gas prices,” said Jeff Hackett, executive vice president of comScore Media Metrix. “Travel sites were also popular during the month as many Americans booked last minute spring break trips and looked ahead to plan summer vacations.”

Americans Paint the Web Green
Year-round tree huggers and gas price-conscious Americans alike had reason to visit Green sites in March. The category drew nearly 20 million visitors during the month, up 11 percent versus February to rank as the top gaining category. Planet Green Sites topped the category with nearly 2.9 million visitors, representing a 24-percent increase from the prior month. Care2.com came in second with 1.9 million visitors, followed by Shine Green with 1.7 million and Mother Nature Network with 1.5 million (up 3 percent). Matter Network grew 37 percent to 985,000 visitors, while EnergyGuide.com saw 870,000 and EPA.gov reached 833,000 (up 17 percent).

Travel Sites Spring into Action
Americans frequented travel sites in March, putting several of the travel subcategories among the top gainers. Travel Information sites attracted more than 61.4 million visitors, up 10 percent from the prior month. TravelAdNetwork took the top spot with 19.9 million visitors (up 8 percent), followed by Yahoo! Travel with 12.6 million (up 22 percent), Tripadvisor Sites with 10.0 million (up 14 percent) and AOL Travel with 6.5 million (up 63 percent).

Car Rental sites grew 9 percent to 6.0 million unique visitors in March, with Enterprise Rent-A-Car Company taking the #1 spot with 3.3 million visitors (up 9 percent) and Avis Budget Group with 1.8 million (up 4 percent). Hertz came in third with 979,000 visitors, followed by Dollar Thrifty Automotive Group, Inc. with 968,000 (up 19 percent) and CarRentals.com with 934,000 (up 31 percent).

Traffic Builds at Home Improvement Sites
Americans browsed Home Improvement sites in March for fresh decorating ideas and gardening tips. More than 49 million people visited the category during the month (up 10 percent vs. February), with eHow Home and Garden taking the top spot with 8.8 million visitors. iVillage Home and Garden drew 6.8 million visitors (up 32 percent), followed by HGTV with 6.1 million (up 13 percent) and Shelterpop with 3.0 million (up 46 percent).

Top 50 Properties
Yahoo! Sites ranked as the #1 property in March with 179.5 million visitors, followed by Google Sites with 176.8 million and Microsoft Sites with 176.4 million. Sites new to the top 50 in March included FoxNews.com (#41), Time Warner (#49) and BuzzMedia (#50).

Top 50 Ad Focus Ranking
Google Ad Network led the March Ad Focus ranking with a reach of 91.7 percent of Americans online, followed by Yahoo! Sites (84.4 percent), Yahoo! Network Plus (83.9 percent) and AOL Advertising (83.8 percent).

About comScore Media Metrix
comScore Media Metrix provides industry-leading Internet audience measurement services that report details of online media usage, visitor demographics and online buying power for the home, work and university audiences across local U.S. markets and across the globe. comScore Media Metrix reports are used by financial analysts, advertising agencies, publishers and marketers. comScore Media Metrix syndicated ratings are based on industry-sanctioned sampling methodologies.

About comScore
comScore, Inc. (NASDAQ: SCOR) is a global leader in measuring the digital world and preferred source of digital business analytics.

The release of eMarketer’s report came on the heels of Yahoo! Search Direct, supposedly to compete with Google Instant Search.

The eMarketer blog post didn’t go into much detail. Here’s their hypothesis:

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