I would still use mariadb or postgresql before mysql.

just because the big boys use it, doesn't mean it's good.

I honestly don't know if that mitigates against a lot of the MongoDB hate you see around here (including my post above). If I was at a place like Stripe and that money to pay Aphyr to battle-test all my database systems and an ops staff the handle all the issues that he found, then I could maybe deploy MongoDB successfully. I'd also have the sort of really, really hard problems that require me to spend that kind of resources on the problem. MongoDB is a much, much worse choice for those of us who DON'T have those needs and resources, though.

It's this funny situation where some engineer starts off using it because it's very convenient to run, and maybe the data model is convenient. You scale it up a bit, debug it, tune it, stuff you'd have to do with any system. At the point when you're sure mongo really sucks, it's too late. The business and even technical management side always prioritizes some other project over replacing it, even though you spend a surprising amount of time each month maintaining the mongodb cluster (performance degredation that compaction doesn't completely fix, and other stuff...).

I get the sense that with 3.0.3 or so, mongodb is a real database now. But it's been years of pain and false advertising. I'd still always vote against it. (Even though at my current place some people started using it for a service... :(