I have so many people that do not want to come to Google+ and some people calling it a failure. It must suck to be on the team at Google in a way because you hear this negative stuff when people have barely given it a chance. 

MySpace never reached this level of popularity.
It took Facebook a very long time to get where Google+ is as well.
Twitter just reached this level in the past few years.

What can be done to get people over from these sites and get them to engage? I think Circles are important and it seems to be something people do not understand. Since this site looks and feels more like a Facebook, it is treated as one, a lot of people expect others to follow them, or for a friend finder system to say oh Joe EveryMan is on here and you went to the same school. That doesn't happen as much. It seems this site is built around interests, are at least that is how I use it. I have 53 circles. Sometimes I share very specific things and other times it is very bland, other times it is cool and important and it goes public, or maybe I just want an opinion from a lot of people. 

The very specific things I share are about food and other such specific topics. I think circles need to get used in a better way for the new people. I also think the mobile app and site need a few changes, nothing major, just a few things to keep it in the loop of tech. +1 on posts is important to me, so is editing, how many times have I spelled a word wrong due to auto correct? 

All this said, I have 600 people circled and I share content as well as comment on content, I use hangouts nightly, usually in 3 or 4 a night. Do not be afraid to hangout, what is the worst that can happen, you may learn something?