It seems that Google + has a raft of other uses for serious networkers. For instance, many people looking to make contacts look through LinkedIn profiles and Twitter followers of authoritative or influential people to find new contacts. Facebook Friends can often also be searched in the same manner.
Google+ offers the same facility. So, find one person on Google+ who works at Google (or AN Other Company) and you can suddenly track down more people from their circles. Because the public profiles often give more than just name of company, you can also find their Twitter accounts, Flickr profile etc.
For some, this may mean that a re-assessment of their privacy settings is required. Just because someone has added you to their circle, it does not mean that you wish to know them. And you have no control over whether they make the members of their circles public or not, meaning that your public profile could become very public, and there does not seem to be any way in which you can make some of your profile information public to certain people and not to others.
This is all about being social but all of a sudden, one can feel that your ability to keep information about yourself private, or not 100% in the public domain, is being eroded.
When posting, you can choose which circle(s) see the post and can also disable resharing by clicking on the arrow at the top right of the post.
Navigate your stream using [j] for down and [k] for up.
Upgrade your broadband connection! If you are in a hangout with 10 people all on webcams, and someone decides to start pulling in Youtube content, your connection may do more than just stutter!