Ruby on Rails

This is my first post here and generally the first post I'm making on the web regarding Ruby or Rails. I come from PHP and especially Joomla. I can't say I have done some "serious" development till now. I've developed small projects but never something 'big'. But these last months I'm very productive and I have a nice idea that I want to develop. So I've searched a lot and decided to go with Ruby & RoR for getting into serious web development. I've started learning Ruby 3 days ago using "Beginning Ruby - From Novice to Professional" by Cooper and I think I'm doing pretty fine till now (just finished the first part).

As I'm eager to learn to develop, I'm constantly thinking about when it will be a good time to start diving into Rails too. I mean, sometimes I can be patient so I don't want to hurt my Ruby knowledge for rushing too soon into Rails. On the other hand, I also don't wanna be too slow on this, cause if I'm to learn Ruby, then when I finish this book I could go on another one (Matz's book) so I will have a solid understanding of all the aspects of the language *before* starting with Rails, but this could take me a lot of time. I just want to do it the "right" way but as Rubyists believe: "there is more than one way to do it" ;)

When would you suggest me to start with Rails? I already have basic knowledge of MVC architecture and classes + objects in Ruby.

Thanks in advance.