Guy, and subsequently, the founders of MS's DRG group (Cam, Brad, Brian, Robert, Alistair, ...) understood the power of this.
Apple used this very effectively with iOS/AppStore.
Marketing is the act of getting someone else to buy something from you.
Evangelism is the act of getting someone else to sell something FOR you.
For example, I employed TE techniques to drive Windows Home Server...
1) They loved the concept of a home server.
2) They hated their actual jobs and wished they were part of a product team.
1) I created an internal program called "Quattro Champions". I gave employees who joined the feeling that they were part of the 'WHS team'. I gave them jobs (e.g. your job is to monitor forums and post goodness). I paid them with a t-shirt and ...
2) I found a few external enthusiasts and did basically the same thing. I made them feel like they were part of the team building the product. That's all I had to do to get them to do a massive amount of work...
This is just one example of a "Technical Evangelism" playbook. When we made Win32 and then COM/OLE happen, we applied the same techniques.
IMO, Technical Evangelism is the ONLY way to achieve scale in getting platform technologies adopted.
The primary reason so few companies do it effectively...
Which brings us full circle on this thread and @halberenson's post.