On this site you will find information about using Doctrine2 for Object Relational Mapping in Joomla!
Today or tomorrow (to be interpreted recursively) we'll provide a package for easy installation. Plug & play... At the moment some unpacked code for the Joomla CMS can be found at https://github.com/jooctrine/jooctrine
Here is a home re-recording I did June 8 of the presentation of June 1 at J & Beyond (reduced to 38 minutes, but now including the first part, that is missing at the JAB-recording):
Slides of presentation on J & Beyond, June 1, 2013:
One of the things I'd like to emphasis and are not on the JAB-video now is transparent persistence (slide 13): the entities don't know anything about persistence, that is decoupled from the model and now the responsability of the mapping layer.
Also see http://en.wikipedia.org/wiki/Persistence_%28computer_science%29#Orthogonal_or_transparent_persistence