Surprised here too at the lack of engagement, but I appreciate your comment...maybe I timed the post wrong :)
We are seeing a fairly strong surge in popularity with Net Promoter within the startup community, but I do think that many people don't understand how deeply NPS relates to those bottom line metrics you mentioned (revenue, LTV, churn, etc). In a predictive fashion no less. Add to that the simplicity from a customers perspective and response rates orders of magnitude higher than traditional research/surveys...powerful stuff.
You correctly noted the challenge of spreading the word (and perhaps benefits) of NPS. I think a lot of that has had to do with the lack of tooling built for this specific purpose, which is something we hope to change in a big way.
Feel free to drop us a note anytime if you'd like to chat further. Would love to get more feedback or answer any other questions you may have.
