One thing that came up in the discussion about some other related offerings (such as Firebase) is the question: "what is your durability story"? When I'm spending the time to store things for my company, I make certain to ask such questions as "is this data important enough to keep on multiple servers, or is having a backup sufficient".

When storing data in services provided and managed by other companies, it becomes more difficult to be certain that the risk tradeoffs are reasonable, as I'm in essence trusting that you aren't just storing the data on a single server in RAM on memcache or something ;P. Some more details would thereby be much appreciated.

(I understand, btw, that I can also have a server keeping a mirror of all of my data, which is definitely awesome, but I also would then want to get a better understanding of whether I would be a fool not to be doing that, or whether I can feel comfortable with having data stored on your servers ;P.)