Thanks for bringing back the section "followers", that is, being able to see who is following us. It was available in the past, and now it is back ;)
yes. Choose the learning, see who comments a lot on discussions(they're always a good source of wisdom), or you can even create a discssion on a specific language sections asking for people to compete with, help, encourage, practice, and so on. By doing this you"ll find Duolingoers, that is, people who work (voluntary) a lot for Duo. That's gonna be a great help!! =)
Followers are people who follow you. Your activity is shown in their stream. Anyone can follow you without your prior consent, this is only done for convenience of reading others' public posts. If someone follows you, you don't have to follow them back if you are not interested in their posts. Anyone can post in your stream even if they don't follow you or you don't follow them.