People rushed to sign up for Google's new social networking service, but they're taking their time returning to the site.

That's the read by Experian Hitwise, which released a report saying Google+ drew 1.8 million total visits last week. More than 10 million people registered for the service after it launched in a limited test starting June 28.

"Everyone was clamoring to get the invites, maybe they're not returning back," said Experian Hitwise spokesman Matt Tatham.

Google+ was the 42nd most visited social network in the U.S. last week.

Facebook drew 1.8 billion visits last week, continuing its status as the most-visited website in the U.S., according to Experian Hitwise.

So far the largest group of Google+ users are typical early adopters. Visitors over the last week were 57 percent male, and the largest group -- 38 percent -- were 18 to 34, according to Experian Hitwise.

The most overall visits to Google+ came from Los Angeles, New York City and San Francisco, but there was a high concentration of visitors from Portland and Bend, Ore., and Bowling Green, Ky.

The greater Seattle area had the ninth highest percentage of visits to Google+ during the four weeks ending July 16.