The MongoHQ API is making great strides moving in this direction and as was mentioned in another post, the team is dog-fooding it so much that they are building the next version of the MongoHQ web app on top of it.

The added benefit that we see is that we are experts in managing, optimizing and scaling all of the backside data structure for you, while offering solid analytics, performance metrics and visual tools that allow you significant control over your data as well as critical insight into what is happening.

Really excited about this type of development going forward and good to see other offerings in the works!

(full disclosure: I am one of the founders of MongoHQ.)