Two days ago I gave a presentation titled "Future is here - Rails and cloud ecosystem". I first talked about what I mean by cloud ecosystem. During the next 45 minutes, we built, published and load tested a real-time note taking application using Ruby on Rails 3 and services like Heroku, MongoHQ, Google Font Directory, Pusher and BrowserMob.
The key message of my presentation is that "whatever you mean by this cloud stuff, the main benefit for me is that I don't spend my energy on building infra — instead I can concentrate on creating awesome applications".
PS: The XSS vulnerability discovered by my wonderful audience was due I used autolink method. Normally, anything like
<%= note.text %> is escaped automatically by Rails 3, but to my surprise `<%= autolink note.text %>` is not.