Symfony 1.4 vs Symfony 2.0 confusion

We are about to start a project and we believe Symfony framework will make our work easier considering our requirements. Our problem is we don't know whether to start our project in Symfony 2.0x or in Symfony 1.4. My choice would 开发者_StackOverflow社区be to start with upgraded version only, but we could not find detailed documentation for symfony 2.0x.

Which is better to use?

If I use Symfony 1.4, can I upgrade to 2.0x easily?

What are the major differences between Symfony 1.4 and Symfony 2.0?

I suggest using 2.0x for the following reasons:

• 2.0x is stable and the newest version.
• the doc is getting bigger every day and there is much going on on the mailinglist.
• upgrading from 1.4 to 2.0x not possible.