Google+ (G+) is a social networking and identity service operated by Google. It started a few months ago like a closed service from where you can’t get out any data and where the only possible interaction (read/write/play) is only possible via the official interfaces (i.e. the web and android clients). Google promised to release a public API and it partly did so tonight, here.
As they stated, “this initial API release is focused on public data only — it lets you read information that people have shared publicly on Google+” (emphasis is mine). So you can already take most of your data out of G+ (note that it was already possible to download your G+ stream with Takeout from the Google Data Liberation Front). As usual, it’s a RESTful API with OAuth authorization. It comes with its own rules and terms (it could be interesting to add to GooDiff). The next step would be to be able to directly write something on Google+.
I only tried to try the examples so far. But unfortunately I got an authorization error. I won’t go further for tonight but their error screen is interesting 🙂