this is marketing cloaked in a developer portal. I think it's great that rethinkdb is trying to distinguish themselves from Mongo, but what's the real marginal utility of a rethinkdb over Mongo?

Mongo has been around for years, and it still has problems.

Rethinkdb is just launching a new product that essentially does the same thing as Mongo, but is maybe just a little easier to use.

I think the Yet Another Database (YAD) question still hasn't been answered by this post.