Yeah, it's long overdue but it is being worked on constantly as we speak. Personally, I would rather wait until it's absolutely finished/watertight and has been tested thoroughly before being released. The last thing we need is a buggy forum ready to be exploited.
I tend to agree, in my opinion and personally I'm used to how the forum looks and works right now. And I believe many other users too.
So for the switch to be successful it needs to be seamless or almost wherever and in whichever way possible.
I am confident once everything is set we will all be enjoying a new forum but I rather wait until it's ready for prime time.