While not all of our developer community happens in Discourse (we have docs, developer tools, conferences, etc. outside of Discourse), probably 70-80% of their experience is here and it is definitely the majority of their experience. We’re constantly getting messages from our community members like this:
Again, they are referring to other things we’ve built for them as well, but they’re largely referring to Discourse 
I’ve also been sharing the value of Discourse to other teams in my business. For example, showing customer success managers that they can see what their customers are doing, and even what they’re doing in a particular period (e.g., what kinds of questions is your customer asking during their onboarding, during their implementation phase, during offboarding). Now, with the new sentiment and emotion modules, I can tell them how their customer feels, or even how they felt at a given time.
I’m new to community as a whole—informally for the last 2 years, and formally with focus for the last 7-8 months. There’s so much I don’t know (in fact, the deeper I go, the more I learn that I don’t know), but I really love that feeling of enabling someone else to be successful in their endeavor.
The plugins we’ve had built, the announcements we make, the community programs we launch, the processes we put in place…it’s so good to see it all amount to something.