Said button wasn’t supposed to be public yet – they essentially let people recommend any online content on Google search.
Google in a blog post said they were still working on such a button:
But the +1 button isn’t just for search results. We’re working on a +1 button that you can put on your pages too, making it easy for people to recommend your content on Google search without leaving your site. If you want to be notified when the +1 button is available for your website, you can sign up for email updates at our +1 webmaster site.
A couple of caveats: +1 not only has to be switched on but you also need an active Google Profile and be logged into it. Schaap says you need to be located in the United States, too, but it – occasionally – works for me and I’m in Belgium.
According to Schaap, the button as such actually functions fine, and interestingly its layout can be modified to be positioned horizontally or vertically. Clicking it makes recommended pages appear in the appropriate tab on your Google Profile page.
UPDATE: Google issued this statement on the button: While we’re thrilled that publishers are anxious to integrate the +1 button into their sites, we’re still working things out and aren’t quite ready for this to be publicly available just yet, so we’re disabling this in the code. Webmasters and other publishers interested in using +1 on their sites should get in touch with us here.
For interesting takes on +1 outside of the TechCrunch network:
Search Engine Land: Meet +1: Google’s Answer To The Facebook Like Button
NewsGrange: Why Google’s +1 Can’t Compete With Facebook’s Like
GigaOm: Sure, I Could Join a Google-Based Social Network — But Why?