To be honest, I can't wait for the Eastern Front to be released, because I want to see what all the creative mapper out there will create from those sweet statics and other content that theatre will bring to FH2.
Releasing French stuff wouldn't hurt too, but it's easy to say from a players perspective, in fact, most of those unreleased weapons and vehicles are in (sometimes very early) WIP state and they still require a lot of codding work to be usable without breaking the balance etc. Releasing them will most likely decrease the FH2 quality, and I believe that's not what developers want.
Most of the new content is being polished right before the releases, and mentioned Segfired Line is a good example of why development process is mostly kept in secret. Sometimes unfinished content has to be abandoned and it's better for the community not to know about it at all.