MongoDB 2.0 Released
I'm curious as to why MongoDB is so popular.  I chose Riak, and my purpose here isn't to bash Mongo, but to understand what was the key feature that made you choose it?Is it pure speed on a single machine?  Is it the query interface?  Something else? Datacenter awareness? Geographic support?The key features that made me choose riak:
- built in distribution/clustering with homogenous nodes
- bitcask had the level of reliability/design that I was looking for.
- better impedance match for what I was doing than CouchDB (which was what I looked at before choosing riak, but couch does view generation when data is added and I need to be able to do it more dynamically.)What sold you on Mongo? What would you most like to improve?(Please don't let this be a debate, I'm more interested in understanding the NoSQL market, what other developers priorities are, etc.)