Great info, thanks! We are using MongoDB for single-server installations and it fits our needs pretty well. Our biggest gripe is that disk space is not freed when collections are dropped, but we can live with it. Other things are just minor inconveniences which plague other DBs too. In our experience MongoDB "just works" - but then again, we don't use its scaling capabilities.
That said, we are looking around to see if there is an even better document-oriented DB available and PostgreSQL looks interesting (with its JSON). Haven't had the chance to try it yet though. Another interesting option is OrientDB (having graph database would be beneficial - but only for small part of our system). Does anyone have experience with other document-oriented storages? (primarily single node usage)
OrientDB is the most interesting alternative to MongoDB with support for Multi-Master replication and relationships: you can decide to embed or link documents:
That said, we are looking around to see if there is an even better document-oriented DB available and PostgreSQL looks interesting (with its JSON). Haven't had the chance to try it yet though. Another interesting option is OrientDB (having graph database would be beneficial - but only for small part of our system). Does anyone have experience with other document-oriented storages? (primarily single node usage)