have users of foursquare run into problems? were they serious? did someone lose money? let's ask. it would answer whether to use an eventually consistent db.
Of course we've run into problems from time to time. No one goes from nothing to foursquare's level of success without running into some bumps along the way.
> were they serious? did someone lose money?
No.
> it would answer whether to use an eventually consistent db
MongoDB actually isn't really an eventually consistent datastore. It doesn't (for example) allow writes to multiple nodes across a network partition and then have a mechanism for resolving conflicts.
You had 11 hours downtime and didn't lose money?
What about opportunity cost? Reputation?
Now you have to share your secret :)
(I guess, if you weren't profitable, you had nothing to lose?)
Stockholm syndrome?
Or perhaps investor pressure to close ranks ;)