I was employed at Google when Google+ launched. Like many Googlers, I tried it out, loved the sharing model, and stuck with the platform. People always joked that Google+ was made up of Googlers, their family, or photographers, but I still enjoyed the engagement I had on Google+ as it typically was a bit better than other places. But after more than 4 years on Google+, is it still the best place for me to share things I find online to spread knowledge and spark conversations w/ people? Thanks to a somewhat popular blog post of mine that I shared on Google+ and Twitter at the same time, I can quantitatively look at engagement between Google+ and Twitter.
Google+
My Google+ post was shared to my Programming collection where I have 9,417 followers. Now according to my Google+ profile I have 5,982 followers, which means I have 3435 people explicitly following my Programming collection (practically all of my 5,982 followers were grandfathered into all of my collections when Google+ introduced the concept). That would suggest that I have 3,435 people who should have a high degree of interest in a blog post that people have told me was interesting and well-written.
What kind of engagement did I have with those 3,435 people (on top of whomever happens to follow me entirely and finds programming interesting)? I got 4 +1s, 1 comment, and no reshares.
My tweet was obviously shared directly to my feed w/ no hashtags. According to my Twitter profile I have 1,390 followers, so 40% as many on Google+ just in my Programming collection, let alone all of the other people who follow all of my Google+ posts.
What kind of engagement did I get with Twitter's fraction of followers? 68 likes, 90 re-tweets, and 6 comments. And this doesn't even cover retweets from other people who directly shared the link and the corresponding interaction from those tweets. So with 40% of the followers I had 17x the appreciation of the share, I actually had re-tweets/shares, and 6x the comments.
Conclusion
It's hard to ignore the discrepancy between the two platforms in terms of engagement (I'm leaving Facebook out since I don't really use it and this is not the kind of stuff I would share on Instagram). While I still appreciate the concept of collections and circles on Google+, I can't ignore the fact that my engagement with people on Twitter in this instance was just so much better (my tweet actually got another like and reshare in the time it took for me to write this). But Twitter's length restrictions drives me nuts and has historically been why I have stayed off of Twitter in the past. I might just have to bite the bullet, though, and put up with the length restriction if I want to engage in more constructive conversations online.