Well, if there isn't going to be a real Doom movie, you can always make do... SJ Zero gave us a link to his first experimental Doom movie, recorded with Doom Legacy v1.29. You can download it at his site.
Snej sent word about his Stop Keen partial conversion. It actually seems to be completed two years before, featuring 22 levels, new textures and sprites. Several screenshots are available as well.
A new site called Add-on Universe has opened, aiming to bring you news about add-ons / skins for a wide variety of games, including the Doom series. However, it's pretty much bare bones right now so you might want to visit at later date.