isnt it round-about that restful-authentication's registration stuff uses observers to send out notification emails? I mean, it sets variables like recently_activated and recently_forgot_password to signal the emails should be sent, and then an observer looks if one of those has been set. But these variables are set in only one place, so it's not really DRYing anything. Seems extra complicated to me. Wouldn't be more straightfoward to just deliver the email directly from the model than set and observe those temporary state variables?
In fact, I'm thinking of stripping them out of the model and moving it up into the controller, so that, for example, admin actions can have the option of generating those emails rather than always being send without control.
What's your strategy for email notifications of events in your application? do you use observers? do you do it in model vs controller?