What is the best MongoDB Object-Document Mapper to use with a Rails?
So I actually first used the Mongo Ruby driver for a pet project at the NYC Techcrunch Disrupt 2010 hackathon. I had a blast using it. Before then, I had been reading up a lot on Mongo but hadn't actually used it. Months after that I did a custom Rails quiz/questionnaire/postest app for tracking clinical trials. I used MongoMapper for that and have loved and used it since. Mongoid is cool, i did have a branch on that project that was using Mongoid instead. In my evaluation MongoMapper made more sense to me. It does stick veyr close to the ruby driver and I like how since version .8, there's a separate gem for querying which is designed specifically for querying MongoDB from the ground up. It wasn't an attempt to recreate activerecord or arel for querying Mongo. So I definitely like that, and plus I actively follow the MongoMapper mailing list. Which is a great resource. Nunemaker and crew are working on the documentation efforts (which aren't as good as Mongoid) but really take one word of advice, read the specs in MongoMapper. They will answer a lot (if not most) of the questions you have about MM. Also, Kyle Banker, who is the author of the Ruby driver (and a really cool guy) seems to be more involved (or aware) of MM development than any other MongoDB ORM/ODM. So that's always a plus.