Okay, so the mere _presence_ of the +1 button in a browser doesn't track visits across the web. But when you press the button, "Google receives information about your Google profile, the URL you +1, your IP address, and other browser-related information."
If you click the button, it lights up in red and also shows up in the +1's tab on your plus.google.com profile (which you can make public or private). Since the +1 button is served from Google's servers and displayed via an iframe, Google of course receives client information when you click it. You're making a request to Google's servers.
It sounds like we're saying the same thing. I just was pointing out that this is all entirely consistent with the entire point of G+ being the "further tracking of what's happening on the internet."