Travel sites have been the largest contributors to online traffic in June 2012, according to comScore. In its monthly analysis of US web activity, the digital measurement company found that ground and cruise travel sites ranked as the top gaining category, growing by 9 percent to 14 million visitors since the previous comparable month.
Amtrak.com took the leading spot in the category with 2.7 million visitors - an increase of 7 percent. This was followed by bus and train company FirstGroup which grew by 22 percent to 2 million visitors. Carnival Cruise Lines followed with nearly 2 million visitors and a rise of 6 percent.
Hotel and Resort sites also scored among the top-gaining traffic categories in June, growing 8 percent to more than 37 million visitors. Hilton Hotels came in first place with 5.5 million visitors, while Marriott was second with 5.4 million visitors.
"June got off to a strong start with significant traffic gains seen at travel and retail sites as Americans readied their free time for the long-awaited summer months," noted Jeff Hackett, executive vice president of comScore, in a press release.
As June's data is revealed, comScore has also expanded its display ad ecosystem reporting. The move is aimed at providing "additional granularity" in the classification of ad publishers, networks and other platforms that comprise the sector, said the company.
Among what it deemed "syndicated Ad Focus entities," Google led the way with an 82 percent reach of Americans online. This was followed by ShareThis with 79 percent. Yahoo sites came in third place with a 76 percent reach, with Facebook next at 72 percent and YouTube.com trailing at 58 percent.
For advertising and buy side networks, Google Ad Network was in top the position with a 93 percent reach, followed by AOL Advertising with 85 percent.

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Melanie White is the Editor of ClickZ, where she has worked since July 2012. White has been with Incisive Media (ClickZ's parent company) since 2009 where she was Deputy Editor/ US Editor for one of the financial risk management titles, International Custody and Fund Administration (later Custody Risk).
In addition, White worked on FX Week where she was a Senior Reporter. She has also worked and contributed to a number of other titles, including The Accountant, International Accounting Bulletin, the New York Post, Independent Magazine (UK), as well as the broadcast title Sunday Live with Adam Boulton at Sky News.
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