But how much do you have done? Or I guess what I'm trying to say, are you at least at the halfway point? Are you in beta testing? Just a rough estimate?
First off, let me say that I am new to this forum, although I have played VF and VF2 on my desktop computer and about a month ago started VF2 on my Android tablet. As a newbie, I just read through this topic in its entirety as well as a few other VF3 topics and my recommendation to you is to do the same. Your question has been answered: when they can project with some certainty, they will update the Previews Page. I could give a link to that, but it is in the post two posts above yours.
I know that peoples' questions about timing are a reflection of excitement and anticipation of a great game. I also know (having worked in commercial software development, although not for a game dev house) that we're unlikely to see a detailed timeline in advance for a number of very good reasons. I can live with that.