IMHO Doctrine 2 unfortunately is a long way off from being ready for Production use, for a few reasons:
- Not any of my client's webserver hosts support PHP 5.3 yet.
- It does fix many problems (cleaner by far), however it does make a lot of things more difficult (no templates, the entity manager).
- It has not reached widespread support yet as Doctrine 1 has. Barely any complete tutorials exist for using Doctrine 2 with Zend Framework.
As much as I'm dying to start using Doctrine 2 with Zend Framework, the above reasons always cause me to fallback on version 1. Perhaps when Zend Framework has reached version 2, then it would make sense.
In the meantime, Doctrine 1 is still a fantastic choice for using with Zend Framework. There are plenty of tutorials, resources and examples. I have it setup with the CMS we deploy, and currently the only long standing issue we have is migrations - however upon investigation it seems to be with our configuration settings.
Unless of course you want to learn Ruby on Rails, Doctrine 1 is by far the best alternative to get you ready for Doctrine 2.