Features added include a sexy query language, scopes, attr_accessible, a fancy cache key helper, a :typecast option for array/set keys, and a bajillion little improvements. Let’s run through each of them just for fun.

John Nunemaker

If you're using the MongoDB document oriented "NoSQL" database from Ruby at all, you owe it to yourself to try John Nunemaker's MongoMapper - it's practically the ActiveRecord of the MongoDB world.

The latest version is a strong step forward. ActiveRecord-esque scoping has been added, and a smart new querying DSL has been implemented that lets you do things like:

User.where(:age.gt => 27).sort(:age).skip(1).limit(1).all

If you're not using MongoDB at all and aren't sure what all the hoopla is about, John's Why I Think Mongo Is To Databases What Rails Was To Frameworks from December 2009 is a great high-level introduction to the concepts involved. I'm using it (and MongoMapper) on coder.io and love it so far.