WebProNews

Compete puts together a monthly ranking of the top 250 Web sites in the US, based on unique visitors, and breaks up the data by relevant categories and behavioral segments. In its latest report, Compete found that the top performers for July fell into four main categories: auto manufacturers that were part of the "Cash for Clunkers" deal, summer blockbuster movie sites, back-to-school shopping sites and social media news aggregates (like Digg or Tweetmeme).

"Marketers need a mechanism for spotting consumer trends as soon as they begin to emerge, especially as the U.S. economy starts down the uncertain road to recovery," says Cynthia Stephens, director of Marketing for Compete.  "The Compete 250 gives marketers a window into online consumer activity and sentiment, which helps them keep a pulse on the market and capitalize on the Internet economy."

Here's a look at the top 50 sites from the 250, followed by the top 20 site traffic gains from June to July:

Sits like Toyota.com, GM.com, and Fordvehicles.com grew by over 20% thanks to the "cash for clunkers" initiative. Blockbusters like Bruno, Ice Age: Dawn of the Dinosaurs, Harry Potter and the Half-Blood Prince, and Transformers 2 led to big boosts in sites like Flixster, Moviefone, and Fandango, while IMDB and Netflix held strong as usual.

Back to school season most likely contributed to an upswing at sites like Walmart.com and Target.com, and the News aggregator and Social Generated news category has just been growing steadily since June 2008.