Ruby on Rails: Do you recommend using Observers?

I notice it's used primarily for sending emails. Let's say I want to send an email after every comment is created.

Is using Observers really necessary when you could just place the Mailer.deliver_e开发者_C百科mail(user) in your comments_controller.rb's create action instead?

For proper programming practices, yes. The observers decouple the code and make sure it stays maintainable.