I'm really glad the JSON changes got in, many thanks to all involved, committers and contributors alike :).
But there's still one feature that's missing to achieve feature parity between the JSON and XML encoding/conversion. And that is the abililty to say in your controller:
@authors = Author.find(:all)
render :json => @authors.to_json(:only => :name)
Please check out this patch that adds this: http://dev.rubyonrails.org/ticket/9751 and help verify it and post any suggestions you may have.
Thanks a lot!
Cheers, Chu Yeow