Within Google+, GoogleBuzz is like a separate feed of whatever you’ve set to automatically go to Buzz (since no one, ever, uses Buzz on purpose). So if your Twitter is set to go to Buzz, it now also goes to your feed on Google+. The same is true for whatever you Buzz on the web. There’s also a +1 feed for whatever you +1. Both of these are separate from what you post “in” Google+ I think this is convenient. I haven’t figured out all of the privacy issues, but +1’s are public by nature. The Photos stream integrates Picasa, which, by the way, can receive automatic uploads (set to private by default) whenever you take a picture on your smart phone.
Google, you are sly. Very, very sly.