What scenario makes more sense - host several EC2 instances with MongoDB installed, or much rather use the Amazon SimpleDB webservice?
When having several EC2 instances with MongoDB I have the problem of setting the instance up by myself.
When using SimpleDB I have the problem of locking me into Amazons data structure right?
What differences are there development-wise? Shouldn't I be able to just switch the DAO of my service layers, to either write to MongoDB or AWS SimpleDB?