So as expected, Google has launched the initial phase of their "Plus" project this week. Since the project is still in beta, not too many people are fully on board to use all it's features. The goal is to turn the project into some sort of Facebook alternative. As it is now, you'll already find the "+1" buttons on various websites, including this one. Once a user clicks the button, the site button will have an increased number. More importantly, search results (including paid ads) will also have that +1.
But those are only the features that everyone has access to. For a more detailed breakdown of all the features available to those in the project, click here.