Nearly a year after Facebook Like buttons spread out across the web, Google has announced its own rival, the +1 button. It launches today as part of Google’s search engine, allowing you to “+1″ the search results and ads that you like. And in a few months, it’ll be arriving at a web site near you.

Is +1 (pronounced “Plus One”) part of the new social network that Google’s long been rumored to be building? Or is +1 simply that “social layer” that Google has said would come and isn’t really meant as a rival to Facebook?

Yes.