The previous branch of symfony, 1.1, was a huge transition for symfony. It introduced the symfony platform, a set of highly decoupled base classes that forms the core of what symfony is built upon. It also introduced the form framework, a subframework within symfony.

On symfony 1.2 technology

Symfony 1.2 starts off where 1.1 left off, by introducing two new subframeworks: One for routing and one for filtering. These new subframeworks make symfony even more powerful and flexible. For instance, the routing framework now is able to support fully restful URLs, and both routing and filtering have the option of using Propel integration. The already existing form framework also got an upgrade, having gotten some nice new features such as automatically nested forms.

Speaking of Propel, the sfPropelPlugin that gets distributed with the framework has been upgraded to Propel 1.3, which means an enormous performance boost as well as some interesting additional features. But perhaps even more important is the fact that you're not bound to Propel anymore out of the box. Symfony 1.2 also comes with Doctrine, an ORM which has a more intuitive API and a similar performance to Propel 1.3.

Another major change is the fact that the admin generator, a tool for easily creating administration interfaces, was refactored to use the new form framework. This is an important step, as it removed the last remnants of the old form system of symfony 1.0, and enables more flexibility in the admin generator.

More information on the new features can be found in the symfony 1.2 announcement as well as the "What's new in symfony 1.2?" tutorial.

Documentation

But the code is not everything that has changed. With the release of symfony 1.2, there's been a tremendous effort to offer symfony users a variation of documentation in several forms:

Jobeet

The Jobeet advent calendar is a new 24-day advent calendar. Every day during december until christmas, a tutorial will be posted. Each tutorial is meant to take about an hour to work through. Together, the full set of tutorials gives you a smooth introduction into symfony. Having done the Jobeet tutorial, you will not be a symfony expert but you will be able to find your way around the framework and know how to build an application using the power of symfony and its components. For people interested in becoming familiar with symfony, this is definitely the recommended way of doing so.

Symfony + Doctrine Book

To celebrate the official inclusion of Doctrine in the framework, a special 7-chapter book was written on the usage of Doctrine and symfony in your project. The symfony + Doctrine book will give you everything you need to work with Doctrine inside your symfony projects. This book is useful both for people starting with Doctrine and as a reference for people who already have experience with the ORM.

Tutorials

With the approach of the symfony 1.2 release, a constant stream of tutorials has been written on the symfony weblog, going into specific details of how to work with the framework. Specifically interesting are the tutorials about Nested Forms, Testing and the RESTful architecture. But there are many more tutorials that you should check out in the symfony weblog.

Concluding

The way I see it, symfony 1.0 was already a really powerful tool for building dynamic web applications. It contained all the functionality for enterprise web application development, but may have been a bit rough on the edges. Symfony 1.1 offered a highly polished version based on a new and strongly improved foundation, that would even allow the symfony platform to be used as a component framework instead of a full-stack framework, creating a flexibility that was required for some situations while still keeping the power of the original version. Symfony 1.2 is clearly showing the shining diamond that symfony is quickly becoming. There are no real sharp edges anymore, so the focus is on polishing the surface to become blindingly shiny. If symfony 1.3 continues on this path, there is a bright future ahead, and I have no reason to think otherwise.