Ditto, I think it is a very good idea. One additional thing I would do is create some sort of "Signup" form so you can collect details of people interested in purchasing once released you could then send a email to once you get the full page up and running.
Kind of opposite to what you said, which I have also had great success with, is when a product isn't made any more, don't delete it, however keep the page and put on it alternative versions of the widget. People still search for years old products.