The Sociable just did a neat little study using Google’s +1 Button Chrome extension and unearthed some surprising insights into the reach of Google’s new stuff-liking button. Most of the sites that get +1s are social networking and tech sites; news and sports don’t get much love.

Google’s own sites get the most +1s, of course, but Facebook is actually closing the gap. While Google Plus has 43,000 +1s, Facebook has 41,000, and that’s up from 36,000 a week ago. Most of the other top sites for +1s are stagnant, though, suggesting that use of the button isn’t growing much outside of early adopters.

The Sociable team used the official extension for Chrome to measure the +1 clicks on the homepages of major sites for 10 days. They covered a range of major categories, including search, email, news, sports and tech.

The predominant finding is that the numbers of +1s aren’t growing very much. Facebook was the only site that gained by any appreciable number. Even though Google Plus saw a 1269% traffic spike over the same period, essentially none of those people clicked +1 on some of the Web’s highest-traffic sites.

It’s no surprise that Google properties are the most +1d, since Google has an interest in splattering the button everywhere. But Google doesn’t seem to be doing a great job of driving its engagement on other sites.

The +1 button launched at the beginning of June, nearly a month before Google Plus opened, but it only reached its full potential at the end of August, when Google turned on +snippets to enable sharing pages to Google Plus. The button is now rolling out to ads, marking the first clear revenue stream for Google’s social network, but The Sociable’s findings are not a great indication of how much users care about +1-ing things.

Thanks to The Sociable for these interesting findings!

Do you use the +1 button to share content on Google Plus?