Google+ invitations to expand
The Google+ invitation button has been available for more than a day now, suggesting Google is loosening up and is more confident about expanding its social network's population. Google+

In the world of the Internet, your success is measured by your reach. That's why sites like Facebook, and Twitter, despite their already massive followings, have moved to place their buttons across other Web sites.

But the search engine giant's Google+ social network, that rolled out its own +1 only one month ago, has already surpassed social stalwart Twitter with regard to buttons.

Fewer than half the largest sites on the Web offer any kind of social link at all on their front page, and these sites represent a massive slice of Internet traffic on any given day, said Jim Yu, CEO of BrightEdge, an enterprise SEO platform provider. The company analyzed the 10,000 largest sites on the Web and found a 33 percent surge in placement for Google's +1 button during the past few weeks.

The company found that +1 buttons are now on 4.4 percent of those sites, up from 3.6 percent in June. Meanwhile, Twitter's plug-ins are displayed on 3.4 percent of the sites.

We would expect to see a land-grab effort this year as plug-ins vie for placement on this very valuable Web real estate, Yu said.

Both Google and Twitter trail far behind Facebook, whose plug-ins, most notably its Like button, are on about 20 percent of the sites' front pages.

Twitter made its tweet button available to publishers last August.

Google declined to comment on the report.