Other factors to consider:

• Expected lifetime of the website
• Other sites at production level are built with Symfony2
  • http://www.exercise.com/
  • http://lichess.org/
• Other web shops starting to use Symfony2
  • http://www.knplabs.com/en/realisations

Symfony 1

Pros

• Knows it very well. Public API as well as internal workings.
• PEAR for plugin management
• Tried tested and true framework
• Lots of plugins off the shelf from the community
• I18N / L10N database for dates, etc complete ICU data
• Well known best practices, naming conventions, configuration framework
• Know what solution fits the job (when to use filters, helpers, extend internal components, etc)
• Lots of documentation, how to’s, guides, tutorials, etc

Cons

• Non xunit testing framework (lime)
• Slower then symfony 2
• End of maintenance 11/2012
• Older technology
• Does not take advantage of PHP 5.3 namespaces

Symfony 2

Pros

• ESI – edge side includes. Big performance boost if used correctly.
• Dependancy Injection and decoupling of modules
• Takes advantage of PHP 5.3 – namespaces, etc. This provides much cleaner code.
• Uses standard logging, etc other components from Zend
• Standardized testing framework (PHPUnit)
• Twig templating seem to provide succinct syntax
• Mongo DB support out of the box
• Doctrine 2

Cons

• New to the team. Learning curve
• Not finished development. Target is March 2011 for final
  • API not stable yet
  • Not as many projects in production
  • No admin generator bundle
• Some modules we need may not be built yet
• Seems like only support for handling install / upgrade / dependancies of bundles in git sub modules. No PEAR2 support (yet?)
• Lack of complete documentation and how to’s
  • http://docs.symfony-reloaded.org/?page=learn

I actually had a small Q&A with symfony creator Fabien Potencier:

Me: Are there plans to integrate Pyrus package management into Symfony 2 for bundles? Is GIT submodules all there is / planned?

Fabien: We have something planned, but it’s too early to talk about it. I can say that the tools will be more flexible than Pyrus and will probably be something on top of it (to be able to install a bundle hosted on Git without the need to create a PEAR package for instance).

Me: Are there plans to create a Jobeet style end-to-end application tutorial? At what date?

Fabien: No. However, a book is being written.

Me: Are there any feature sets of Symfony 2 that are lacking compared to the more mature symfony 1?

Fabien: The admin generator. But that’s something we will work on soon.

Me: Does Symfony 2 have a supported way to handle an asset CDN other then a hack like the override of “_compute_public_path()” helper in symfony 1?

Fabien: Yes, it is supported out of the box.