Yes, I got caught red-handed with my NoDB/gunDB marketing speak. Pretty embarrassing, but the point is that it is a distributed persisted cache, so you get the benefits of a DB without having to manage or maintain a DB.

You are right, most businesses that run that type of logic probably have the money to afford configuring master-slave based systems. They probably should not move over to GUN.

No, you do not have to use S3 for persistence, you can also use your disk. Persistence is a plugin in GUN, so you could build your own module that uses anything to store data.

However, there are lots of interesting advantages to distributed/decentralized master-master systems. And I'm trying to make those algorithms available to common man.

Thanks for the encouragement, I'll be adding more docs and blogs and stuff.

Edit: This person (in the comments below, please upvote him), and my reply, best addresses the most important questions: https://news.ycombinator.com/item?id=9077969